kopia lustrzana https://github.com/micropython/micropython
docs: Add quickref and docs for mimxrt, including network.LAN docs.
robert-hh
Damien George
rodzic
71344c15f4
commit
7a447e08b2
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@ -12,6 +12,7 @@ MicroPython documentation and references
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esp8266/quickref.rst
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esp32/quickref.rst
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rp2/quickref.rst
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mimxrt/quickref.rst
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wipy/quickref.rst
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unix/quickref.rst
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zephyr/quickref.rst
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@ -78,6 +78,13 @@ Methods
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With a single *value* argument the pulse width is set to that value.
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Specific PWM class implementations
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----------------------------------
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The following concrete class(es) implement enhancements to the PWM class.
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| :ref:`pyb.Timer for PyBoard <pyb.Timer>`
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Limitations of PWM
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------------------
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@ -90,6 +97,11 @@ Limitations of PWM
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80000000 / 267 = 299625.5 Hz, not 300kHz. If the divider is set to 266 then
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the PWM frequency will be 80000000 / 266 = 300751.9 Hz, but again not 300kHz.
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Some ports like the RP2040 one use a fractional divider, which allow a finer
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granularity of the frequency at higher frequencies by switching the PWM
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pulse duration between two adjacent values, such that the resulting average
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frequency is more close to the intended one, at the cost of spectral purity.
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* The duty cycle has the same discrete nature and its absolute accuracy is not
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achievable. On most hardware platforms the duty will be applied at the next
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frequency period. Therefore, you should wait more than "1/frequency" before
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@ -122,3 +122,46 @@ You can set the pins used for SPI access by passing a tuple as the
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*Note:* The current cc3200 SD card implementation names the this class
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:class:`machine.SD` rather than :class:`machine.SDCard` .
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mimxrt
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``````
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The SDCard module for the mimxrt port only supports access via dedicated SD/MMC
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peripheral (USDHC) in 4-bit mode with 50MHz clock frequency exclusively.
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Unfortunately the MIMXRT1011 controller does not support the USDHC peripheral.
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Hence this controller does not feature the ``machine.SDCard`` module.
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Due to the decision to only support 4-bit mode with 50MHz clock frequency the
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interface has been simplified, and the constructor signature is:
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.. class:: SDCard(slot=1)
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:noindex:
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The pins used for the USDHC peripheral have to be configured in ``mpconfigboard.h``.
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Most of the controllers supported by the mimxrt port provide up to two USDHC
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peripherals. Therefore the pin configuration is performed using the macro
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``MICROPY_USDHCx`` with x being 1 or 2 respectively.
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The following shows an example configuration for USDHC1::
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#define MICROPY_USDHC1 \
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{ \
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.cmd = { GPIO_SD_B0_02_USDHC1_CMD}, \
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.clk = { GPIO_SD_B0_03_USDHC1_CLK }, \
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.cd_b = { GPIO_SD_B0_06_USDHC1_CD_B },\
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.data0 = { GPIO_SD_B0_04_USDHC1_DATA0 },\
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.data1 = { GPIO_SD_B0_05_USDHC1_DATA1 },\
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.data2 = { GPIO_SD_B0_00_USDHC1_DATA2 },\
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.data3 = { GPIO_SD_B0_01_USDHC1_DATA3 },\
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}
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If the card detect pin is not used (cb_b pin) then the respective entry has to be
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filled with the following dummy value::
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#define USDHC_DUMMY_PIN NULL , 0
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Based on the definition of macro ``MICROPY_USDHC1`` and/or ``MICROPY_USDHC2``
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the ``machine.SDCard`` module either supports one or two slots. If only one of
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the defines is provided, calling ``machine.SDCard()`` or ``machine.SDCard(1)``
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will return an instance using the respective USDHC peripheral. When both macros
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are defined, calling ``machine.SDCard(2)`` returns an instance using USDHC2.
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@ -0,0 +1,93 @@
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.. currentmodule:: network
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.. _network.LAN:
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class LAN -- control an Ethernet module
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=======================================
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This class allows you to control the Ethernet interface. The PHY hardware type is board-specific.
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Example usage::
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import network
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nic = network.LAN(0)
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print(nic.ifconfig())
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# now use socket as usual
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...
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Constructors
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------------
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.. class:: LAN(id, *, phy_type=<board_default>, phy_addr=<board_default>, phy_clock=<board_default>)
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Create a LAN driver object, initialise the LAN module using the given
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PHY driver name, and return the LAN object.
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Arguments are:
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- *id* is the number of the Ethernet port, either 0 or 1.
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- *phy_type* is the name of the PHY driver. For most board the on-board PHY has to be used and
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is the default. Suitable values are port specific.
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- *phy_addr* specifies the address of the PHY interface. As with *phy_type*, the hardwired value has
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to be used for most boards and that value is the default.
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- *phy_clock* specifies, whether the data clock is provided by the Ethernet controller or the PYH interface.
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The default value is the one that matches the board. If set to ``True``, the clock is driven by the
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Ethernet controller, otherwise by the PHY interface.
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For example, with the Seeed Arch Mix board you can use::
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nic = LAN(0, phy_type=LAN.PHY_LAN8720, phy_addr=2, phy_clock=False)
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Methods
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-------
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.. method:: LAN.active([state])
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With a parameter, it sets the interface active if *state* is true, otherwise it
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sets it inactive.
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Without a parameter, it returns the state.
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.. method:: LAN.isconnected()
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Returns ``True`` if the physical Ethernet link is connected and up.
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Returns ``False`` otherwise.
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.. method:: LAN.status()
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Returns the LAN status.
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.. method:: LAN.ifconfig([(ip, subnet, gateway, dns)])
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Get/set IP address, subnet mask, gateway and DNS.
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When called with no arguments, this method returns a 4-tuple with the above information.
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To set the above values, pass a 4-tuple with the required information. For example::
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nic.ifconfig(('192.168.0.4', '255.255.255.0', '192.168.0.1', '8.8.8.8'))
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.. method:: LAN.config(config_parameters)
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Sets or gets parameters of the LAN interface. The only parameter that can be
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retrieved is the MAC address, using::
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mac = LAN.config("mac")
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The parameters that can be set are:
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- ``trace=n`` sets trace levels; suitable values are:
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- 2: trace TX
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- 4: trace RX
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- 8: full trace
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- ``low_power=bool`` sets or clears low power mode, valid values being ``False``
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or ``True``.
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Specific LAN class implementations
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----------------------------------
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On the mimxrt port, suitable values for the *phy_type* constructor argument are:
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``PHY_KSZ8081``, ``PHY_DP83825``, ``PHY_DP83848``, ``PHY_LAN8720``, ``PHY_RTL8211F``.
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@ -152,6 +152,7 @@ provide a way to control networking interfaces of various kinds.
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network.WLANWiPy.rst
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network.CC3K.rst
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network.WIZNET5K.rst
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network.LAN.rst
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Network functions
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=================
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@ -0,0 +1,92 @@
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.. _mimxrt_general:
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General information about the MIMXRT port
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=========================================
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The i.MXRT MCU family is a high performance family of devices made by NXP.
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Based on an ARM7 core, they provide many on-chip I/O units for building
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small to medium sized devices.
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Multitude of boards
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-------------------
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There is a multitude of modules and boards from different sources which carry
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an i.MXRT chip. MicroPython aims to provide a generic port which runs on
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as many boards/modules as possible, but there may be limitations. The
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NXP IMXRT1020-EVK and the Teensy 4.0 and Teensy 4.1 development boards are taken
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as reference for the port (for example, testing is performed on them).
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For any board you are using please make sure you have a data sheet, schematics
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and other reference materials so you can look up any board-specific functions.
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The following boards are supported by the port:
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- MIMXRT1010-EVK
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- MIMXRT1020-EVK
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- MIMXRT1050-EVK
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- MIMXRT1060-EVK
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- MIMXRT1064-EVK
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- Teensy 4.0
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- Teensy 4.1
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Supported MCUs
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--------------
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+-------------+--------------------+-------------------------+
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| Product | CPU | Memory |
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+=============+====================+=========================+
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| i.MX RT1064 | Cortex-M7 @600 MHz | 1 MB SRAM, 4 MB Flash |
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+-------------+--------------------+-------------------------+
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| i.MX RT1061 | Cortex-M7 @600 MHz | 1 MB SRAM |
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+-------------+--------------------+-------------------------+
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| i.MX RT1062 | Cortex-M7 @600 MHz | 1 MB SRAM |
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+-------------+--------------------+-------------------------+
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| i.MX RT1050 | Cortex-M7 @600 MHz | 512 kB SRAM |
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+-------------+--------------------+-------------------------+
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| i.MX RT1020 | Cortex-M7 @500 MHz | 256 kB SRAM |
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+-------------+--------------------+-------------------------+
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| i.MX RT1010 | Cortex-M7 @500 MHz | 128 kB SRAM |
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+-------------+--------------------+-------------------------+
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Note: Most of the controllers do not have internal flash memory. Therefore
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their flash capacity is dependent on an external flash chip.
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To make a generic MIMXRT port and support as many boards as possible the
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following design and implementation decision were made:
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* GPIO pin numbering is based on the board numbering as well as on the
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MCU numbering. Please have the manual/pin diagram of your board at hand
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to find correspondence between your board pins and actual i.MXRT pins.
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* All MCU pins are supported by MicroPython but not all are usable on any given board.
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Technical specifications and SoC datasheets
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-------------------------------------------
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The data sheets and other reference material for i.MXRT chip are available
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from the vendor site: https://www.nxp.com/products/processors-and-microcontrollers/arm-microcontrollers/i-mx-rt-crossover-mcus:IMX-RT-SERIES .
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They are the primary reference for the chip technical specifications, capabilities,
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operating modes, internal functioning, etc.
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For your convenience, a few technical specifications are provided below:
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* Architecture: ARM Cortex M7
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* CPU frequency: up to 600MHz
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* Total RAM available: up to 1 MByte (see table)
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* BootROM: 96KB
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* External FlashROM: code and data, via SPI Flash; usual size 2 - 8 MB
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Some boards provide additional external RAM and SPI flash.
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* GPIO: up to 124 (GPIOs are multiplexed with other functions, including
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external FlashROM, UART, etc.)
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* UART: 4 or 8 RX/TX UART. Hardware handshaking is supported by the MCU,
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but the boards used for testing do not expose the signals.
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* SPI: 2 or 4 low power SPI interfaces (software implementation available on every pin)
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* I2C: 2 or 4 low power I2C interfaces (software implementation available on every pin)
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* I2S: 3 I2S interfaces
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* ADC: one or two 12-bit SAR ADC converters
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* Ethernet controller
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* Programming: using BootROM bootloader from USB - due to external FlashROM
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and always-available BootROM bootloader, the MIMXRT is not brickable
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The lower numbers for UART, SPI and I2C apply to the i.MXRT 101x MCU.
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For more information see the i.MXRT data sheets or reference manuals.
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NXP provides software support through it's SDK packages.
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Plik binarny nie jest wyświetlany.
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Po Szerokość: | Wysokość: | Rozmiar: 125 KiB |
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@ -0,0 +1,864 @@
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.. _mimxrt_quickref:
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Quick reference for the i.MXRT family
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=====================================
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.. image:: img/teensy_4.1.jpg
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:alt: Teensy 4.1 board
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:width: 640px
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The Teensy 4.1 board.
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Below is a quick reference for i.MXRT-based boards. If it is your first time
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working with this board it may be useful to get an overview of the microcontroller:
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.. toctree::
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:maxdepth: 1
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general.rst
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tutorial/intro.rst
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Installing MicroPython
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----------------------
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See the corresponding section of tutorial: :ref:`mimxrt_intro`. It also includes
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a troubleshooting subsection.
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General board control
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---------------------
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The MicroPython REPL is on the USB port, configured in VCP mode.
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Tab-completion is useful to find out what methods an object has.
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Paste mode (ctrl-E) is useful to paste a large slab of Python code into
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the REPL.
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The :mod:`machine` module::
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import machine
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machine.freq() # get the current frequency of the CPU
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Delay and timing
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----------------
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Use the :mod:`time <time>` module::
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import time
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time.sleep(1) # sleep for 1 second
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time.sleep_ms(500) # sleep for 500 milliseconds
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time.sleep_us(10) # sleep for 10 microseconds
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start = time.ticks_ms() # get millisecond counter
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delta = time.ticks_diff(time.ticks_ms(), start) # compute time difference
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Timers
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------
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The i.MXRT port has three hardware timers. Use the :ref:`machine.Timer <machine.Timer>` class
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with a timer ID from 0 to 2 (inclusive)::
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from machine import Timer
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tim0 = Timer(0)
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tim0.init(period=5000, mode=Timer.ONE_SHOT, callback=lambda t:print(0))
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tim1 = Timer(1)
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tim1.init(period=2000, mode=Timer.PERIODIC, callback=lambda t:print(1))
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The period is in milliseconds.
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Virtual timers are not currently supported on this port.
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.. _mimxrt_Pins_and_GPIO:
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Pins and GPIO
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-------------
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Use the :ref:`machine.Pin <machine.Pin>` class::
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from machine import Pin
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p0 = Pin('D0', Pin.OUT) # create output pin on GPIO0
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p0.on() # set pin to "on" (high) level
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p0.off() # set pin to "off" (low) level
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p0.value(1) # set pin to on/high
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p2 = Pin('D2', Pin.IN) # create input pin on GPIO2
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print(p2.value()) # get value, 0 or 1
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p4 = Pin('D4', Pin.IN, Pin.PULL_UP) # enable internal pull-up resistor
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p5 = Pin('D5', Pin.OUT, value=1) # set pin high on creation
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p6 = Pin(pin.cpu.GPIO_B1_15, Pin.OUT) # Use the cpu pin name.
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Available Pins follow the ranges and labelling of the respective board, like:
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- 0-33 for Teensy 4.0,
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- 0-21 for the MIMXRT10xx-EVK board, or 'D0-Dxx', or 'A0-Ann',
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- 0-14 for the Olimex RT1010Py board, or 'D0'-'Dxx' and 'A0'-'Ann'
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- 'J3_xx', 'J4_xx', 'J5_xx' for the Seeed ARCH MIX board,
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or the pin names of the Pin.board or Pin.cpu classes.
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Notes:
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* The MIMXRT1xxx-EVK boards may have other on-board devices connected to these
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pins, limiting it's use for input or output.
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* At the MIMXRT1010_EVK, pins D4, D5 and D9 of the Arduino connector are by
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default not connected to the MCU. For details refer to the schematics.
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* At the MIMXRT1170_EVK board, the inner rows of the Arduino connectors are assigned as follows:
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- D16 - D23: J9, odd pin numbers; D17 is by default not connected.
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- D24 - D27: J26, odd pin numbers; J63-J66 have to be closed to enable these pins.
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- D29 - D36: J25, odd pin numbers; D29 and D30 are by default not connected.
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There's a higher-level abstraction :ref:`machine.Signal <machine.Signal>`
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which can be used to invert a pin. Useful for illuminating active-low LEDs
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using ``on()`` or ``value(1)``.
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UART (serial bus)
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-----------------
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See :ref:`machine.UART <machine.UART>`. ::
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from machine import UART
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uart1 = UART(1, baudrate=115200)
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uart1.write('hello') # write 5 bytes
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uart1.read(5) # read up to 5 bytes
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The i.MXRT has up to eight hardware UARTs, but not every board exposes all
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TX and RX pins for users. The pin assignment of UARTs to pins is fixed.
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The UARTs are numbered 1..8. The rx/tx pins are assigned according to the
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tables below:
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================ =========== =========== =========== ===========
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Board / Pin UART0 UART1 UART2 UART3
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================ =========== =========== =========== ===========
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Teensy 4.0 - 0/1 7/8 14/15
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Teensy 4.1 - 0/1 7/8 14/15
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MIMXRT1010-EVK Debug USB D0/D1 D7/D6 -
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MIMXRT1015-EVK Debug USB D0/D1 D7/A1 -
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MIMXRT1020-EVK Debug USB D0/D1 D9/D6 D10/D13
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MIMXRT1050-EVK Debug USB D0/D1 D7/D6 D8/D9
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MIMXRT1050-EVKB Debug USB D0/D1 D7/D6 D8/D9
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MIMXRT1060-EVK Debug USB D0/D1 D7/D6 D8/D9
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MIMXRT1064-EVK Debug USB D0/D1 D7/D6 D8/D9
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MIMXRT1170-EVK Debug USB D0/D1 D12/D11 D10/D13
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Olimex RT1010Py - RxD/TxD D5/D6 -
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Seeed ARCH MIX - J3_19/J3_20 J4_16/J4_17 J4_06/J4_07
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================ =========== =========== =========== ===========
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================ =========== =========== ======= ======= =====
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Board / Pin UART4 UART5 UART6 UART7 UART8
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================ =========== =========== ======= ======= =====
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Teensy 4.0 16/17 21/20 25/24 28/29 -
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Teensy 4.1 16/17 21/20 25/24 28/29 34/35
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MIMXRT1010-EVK - - - - -
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MIMXRT1015-EVK - - - - -
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MIMXRT1020-EVK D15/D14 A1/A0 - - -
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||||
MIMXRT1050-EVK A1/A0 - - - -
|
||||
MIMXRT1050-EVKB A1/A0 - - - -
|
||||
MIMXRT1060-EVK A1/A0 - - - -
|
||||
MIMXRT1064-EVK A1/A0 - - - -
|
||||
MIMXRT1170-EVK D15/D14 D25/D26 D33/D34 D35/D36 -
|
||||
Olimex RT1010Py - - - - -
|
||||
Seeed ARCH MIX J4_10/J4_11 J5_08/J5_12 - - -
|
||||
================ =========== =========== ======= ======= =====
|
||||
|
||||
PWM (pulse width modulation)
|
||||
----------------------------
|
||||
|
||||
The i.MXRT has up to four dedicated PWM modules with four FLEXPWM submodules each
|
||||
and up to four QTMR modules with four channels, which can be used to generate
|
||||
a PWM signal or signal pair.
|
||||
|
||||
The PWM functions are provided by the :ref:`machine.PWM <machine.PWM>` class.
|
||||
It supports all basic methods listed for that class and a few additional methods for
|
||||
handling signal groups. ::
|
||||
|
||||
# Samples for Teensy
|
||||
#
|
||||
|
||||
from machine import Pin, PWM
|
||||
|
||||
pwm2 = PWM(Pin(2)) # create PWM object from a pin
|
||||
pwm2.freq() # get current frequency
|
||||
pwm2.freq(1000) # set frequency
|
||||
pwm2.duty_u16() # get current duty cycle, range 0-65535
|
||||
pwm2.duty_u16(200) # set duty cycle, range 0-65535
|
||||
pwm2.deinit() # turn off PWM on the pin
|
||||
# create a complementary signal pair on Pin 2 and 3
|
||||
pwm2 = PWM((2, 3), freq=2000, duty_ns=20000)
|
||||
|
||||
# Create a group of four synchronized signals.
|
||||
# Start with Pin(4) at submodule 0, which creates the sync pulse.
|
||||
pwm4 = PWM(Pin(4), freq=1000, align=PWM.HEAD)
|
||||
# Pins 5, 6, and 9 are pins at the same module
|
||||
pwm5 = PWM(Pin(5), freq=1000, duty_u16=10000, align=PWM.HEAD, sync=True)
|
||||
pwm6 = PWM(Pin(6), freq=1000, duty_u16=20000, align=PWM.HEAD, sync=True)
|
||||
pwm9 = PWM(Pin(9), freq=1000, duty_u16=30000, align=PWM.HEAD, sync=True)
|
||||
|
||||
pwm3 # show the PWM objects properties
|
||||
|
||||
|
||||
PWM Constructor
|
||||
```````````````
|
||||
|
||||
.. class:: PWM(dest, freq, duty_u16, duty_ns, *, center, align, invert, sync, xor, deadtime)
|
||||
:noindex:
|
||||
|
||||
Construct and return a new PWM object using the following parameters:
|
||||
|
||||
- *dest* is the entity on which the PWM is output, which is usually a
|
||||
:ref:`machine.Pin <machine.Pin>` object, but a port may allow other values,
|
||||
like integers or strings, which designate a Pin in the machine.PIN class.
|
||||
*dest* is either a single object or a two element object tuple.
|
||||
If the object tuple is specified, the two pins act in complementary
|
||||
mode. These two pins must be the A/B channels of the same submodule.
|
||||
|
||||
PWM objects are either provided by a FLEXPWM module or a QTMR module.
|
||||
The i.MXRT devices have either two or four FLEXPWM and QTMR modules.
|
||||
Each FLEXPWM module has four submodules with three channels, each,
|
||||
called A, B and X. Each QTMR module has four channels.
|
||||
Each FLEXPWM submodule or QTMR channel may be set to different parameters.
|
||||
Not every channel is routed to a board pin. Details are listed below.
|
||||
|
||||
Setting *freq* affects the three channels of the same FLEXPWM submodule.
|
||||
Only one of *duty_u16* and *duty_ns* should be specified at a time.
|
||||
|
||||
Keyword arguments:
|
||||
|
||||
- *freq* should be an integer which sets the frequency in Hz for the
|
||||
PWM cycle. The valid frequency range is 15 Hz resp. 18Hz resp. 24Hz up to > 1 MHz.
|
||||
- *duty_u16* sets the duty cycle as a ratio ``duty_u16 / 65536``.
|
||||
The duty cycle of a X channel can only be changed, if the A and B channel
|
||||
of the respective submodule is not used. Otherwise the duty_16 value of the
|
||||
X channel is 32768 (50%).
|
||||
- *duty_ns* sets the pulse width in nanoseconds. The limitation for X channels
|
||||
apply as well.
|
||||
- *center*\=value. An integer sets the center of the pulse within the pulse period.
|
||||
The range is 0-65535. The resulting pulse will last from center - duty_u16/2 to
|
||||
center + duty_u16/2.
|
||||
- *align*\=value. Shortcuts for the pulse center setting, causing the pulse either at
|
||||
the center of the frame (value=0), the leading edge at the begin (value=1) or the
|
||||
trailing edge at the end of a pulse period (value=2).
|
||||
- *invert*\=True|False channel_mask. Setting a bit in the mask inverts the respective channel.
|
||||
Bit 0 inverts the first specified channel, bit 2 the second. The default is 0.
|
||||
- *sync*\=True|False. If a channel of a module's submodule 0 is already active, other
|
||||
submodules of the same module can be forced to be synchronous to submodule 0. Their
|
||||
pulse period start then at at same clock cycle. The default is False.
|
||||
- *xor*\=0|1|2. If set to 1 or 2, the channel will output the XOR'd signal from channels
|
||||
A or B. If set to 1 on channel A or B, both A and B will show the same signal. If set
|
||||
to 2, A and B will show alternating signals. For details and an illustration, please
|
||||
refer to the MCU's reference manual, chapter "Double Switching PWMs".
|
||||
- *deadtime*\=time_ns. This setting affects complementary channels and defines a deadtime
|
||||
between an edge of a first channel and the edge of the next channel, in which both
|
||||
channels are set to low. That allows connected H-bridges to switch off one side
|
||||
of a push-pull driver before switching on the other side.
|
||||
|
||||
PWM Methods
|
||||
```````````
|
||||
|
||||
The methods are identical to the generic :ref:`machine.PWM <machine.PWM>` class,
|
||||
with additional keyword arguments to the init() method, matchings those of the constructor.
|
||||
|
||||
Each FLEX submodule or QTMR module may run at different frequencies. The PWM signal
|
||||
is created by dividing the pwm_clk signal by an integral factor, according to the formula::
|
||||
|
||||
f = pwm_clk / (2**n * m)
|
||||
|
||||
with n being in the range of 0..7, and m in the range of 2..65536. pmw_clk is 125Mhz
|
||||
for MIMXRT1010/1015/1020, 150 MHz for MIMXRT1050/1060/1064 and 160MHz for MIMXRT1170.
|
||||
The lowest frequency is pwm_clk/2**23 (15, 18, 20Hz). The highest frequency with
|
||||
U16 resolution is pwm_clk/2**16 (1907, 2288, 2441 Hz), the highest frequency
|
||||
with 1 percent resolution is pwm_clk/100 (1.25, 1.5, 1.6 MHz). The highest achievable
|
||||
frequency is pwm_clk/3 for the A/B channels, and pwm_clk/2 for the X channels and QTMR
|
||||
signal.
|
||||
|
||||
PWM Pin Assignment
|
||||
``````````````````
|
||||
|
||||
Pins are specified in the same way as for the Pin class. The following tables show
|
||||
the assignment of the board Pins to PWM modules:
|
||||
|
||||
=========== ========== ========== ====== ============== ======
|
||||
Pin/ MIMXRT 1010 1015 1020 1050/1060/1064 1170
|
||||
=========== ========== ========== ====== ============== ======
|
||||
D0 - Q1/1 F1/1/B - -
|
||||
D1 - Q1/0 F1/1/A - -
|
||||
D2 F1/3/B F1/3/A - F1/3/B -
|
||||
D3 F1/3/A F1/0/A F2/3/B F4/0/A F1/2/A
|
||||
D4 F1/3/A (*) Q1/2 Q2/1 F2/3/A Q4/2
|
||||
D5 F1/0/B (*) F1/0/B F2/3/A F1/3/A F1/2/B
|
||||
D6 - F1/2/B F2/0/A Q3/2 F1/0/A
|
||||
D7 - - F1/0/A Q3/3 -
|
||||
D8 F1/0/A F1/1/B F1/0/B F1/1/X Q4/3
|
||||
D9 F1/1/B (*) F1/2/A F2/0/B F1/0/X F1/0/B
|
||||
D10 F1/3/B - F2/2/B F1/0/B (*) F2/2/B
|
||||
D11 F1/2/A - F2/1/A F1/1/A (*) -
|
||||
D12 F1/2/B - F2/1/B F1/1/B (*) -
|
||||
D13 F1/3/A - F2/2/A F1/0/A (*) F2/2/A
|
||||
D14 F1/0/B - - F2/3/B -
|
||||
D15 F1/0/A - - F2/3/A -
|
||||
A0 - - F1/2/A - -
|
||||
A1 F1/3/X F1/3/B F1/2/B - -
|
||||
A2 F1/2/X F1/3/A F1/3/A - -
|
||||
A3 - F1/2/A F1/3/B - -
|
||||
A4 - - - Q3/1 -
|
||||
A5 - - - Q3/0 -
|
||||
D31 - - - - F1/2/B
|
||||
D32 - - - - F1/2/A
|
||||
D33 - - - - F1/1/B
|
||||
D34 - - - - F1/1/A
|
||||
D35 - - - - F1/0/B
|
||||
D36 - - - - F1/0/A
|
||||
=========== ========== ========== ====== ============== ======
|
||||
|
||||
Pins denoted with (*) are by default not wired at the board.
|
||||
|
||||
==== ========== ==== ==========
|
||||
Pin Teensy 4.0 Pin Teensy 4.1
|
||||
==== ========== ==== ==========
|
||||
0 F1/1/X 0 F1/1/X
|
||||
1 F1/0/X 1 F1/0/X
|
||||
2 F4/2/A 2 F4/2/A
|
||||
3 F4/2/B 3 F4/2/B
|
||||
4 F2/0/A 4 F2/0/A
|
||||
5 F2/1/A 5 F2/1/A
|
||||
6 F2/2/A 6 F2/2/A
|
||||
7 F1/3/B 7 F1/3/B
|
||||
8 F1/3/A 8 F1/3/A
|
||||
9 F2/2/B 9 F2/2/B
|
||||
10 Q1/0 10 Q1/0
|
||||
11 Q1/2 11 Q1/2
|
||||
12 Q1/1 12 Q1/1
|
||||
13 Q2/0 13 Q2/0
|
||||
14 Q3/2 14 Q3/2
|
||||
15 Q3/3 15 Q3/3
|
||||
18 Q3/1 18 Q3/1
|
||||
19 Q3/0 19 Q3/0
|
||||
22 F4/0/A 22 F4/0/A
|
||||
23 F4/1/A 23 F4/1/A
|
||||
24 F1/2/X 24 F1/2/X
|
||||
25 F1/3/X 25 F1/3/X
|
||||
28 F3/1/B 28 F3/1/B
|
||||
29 F3/1/A 29 F3/1/A
|
||||
33 F2/0/B 33 F2/0/B
|
||||
- - 36 F2/3/A
|
||||
- - 37 F2/3/B
|
||||
DAT1 F1/1/B 42 F1/1/B
|
||||
DAT0 F1/1/A 43 F1/1/A
|
||||
CLK F1/0/B 44 F1/0/B
|
||||
CMD F1/0/A 45 F1/0/A
|
||||
DAT2 F1/2/A 46 F1/2/A
|
||||
DAT3 F1/2/B 47 F1/2/B
|
||||
- - 48 F1/0/B
|
||||
- - 49 F1/2/A
|
||||
- - 50 F1/2/B
|
||||
- - 51 F3/3/B
|
||||
- - 52 F1/1/B
|
||||
- - 53 F1/1/A
|
||||
- - 54 F3/0/A
|
||||
==== ========== ==== ==========
|
||||
|
||||
========= ==============
|
||||
Pin Seeed ARCH MIX
|
||||
========= ==============
|
||||
J3_04 Q4/3
|
||||
J3_10 Q1/3
|
||||
J3_12 Q2/3
|
||||
J3_13 Q3/3
|
||||
J3_16 Q3/0
|
||||
J3_17 Q3/1
|
||||
J3_19 F1/3/X
|
||||
J3_20 F1/2/X
|
||||
J4_08 F4/0/A
|
||||
J4_09 F4/1/A
|
||||
J4_16 Q3/2
|
||||
J4_17 Q3/3
|
||||
J5_32 Q1/0
|
||||
J5_28 Q1/1
|
||||
J5_29 Q1/2
|
||||
J5_30 Q2/0
|
||||
J5_04 Q2/1
|
||||
J5_05 Q2/3
|
||||
J5_06 F2/0/A
|
||||
J5_07 F2/0/B
|
||||
J5_08 F2/1/A
|
||||
J5_12 F2/1/B
|
||||
J5_13 F2/2/A
|
||||
J5_14 F2/2/B
|
||||
J5_23 F1/3/A
|
||||
J5_24 F1/3/B
|
||||
J5_25 F2/3/A
|
||||
J5_26 F2/3/B
|
||||
J5_42 Q3/0
|
||||
J5_43 Q3/1
|
||||
J5_50 F1/0/X
|
||||
LED_RED F2/3/A
|
||||
LED_GREEN F1/3/A
|
||||
LED_BLUE F1/3/B
|
||||
========= ==============
|
||||
|
||||
========= ===============
|
||||
Pin Olimex RT1010PY
|
||||
========= ===============
|
||||
D0 -
|
||||
D1 F1/0/B
|
||||
D2 F1/0/A
|
||||
D3 F1/1/B
|
||||
D4 F1/1/A
|
||||
D5 F1/2/B
|
||||
D6 F1/2/A
|
||||
D7 F1/3/B
|
||||
D8 F1/3/A
|
||||
D9 -
|
||||
D10 F1/0/B
|
||||
D11 F1/0/A
|
||||
D12 F1/1/B
|
||||
D13 F1/1/A
|
||||
D14 -
|
||||
A0 -
|
||||
A1 F1/2/B
|
||||
A2 F1/2/A
|
||||
A3 F1/3/B
|
||||
A4 F1/3/A
|
||||
SDI F1/3/X
|
||||
SDO F1/2/X
|
||||
CS0 F1/1/X
|
||||
SCK F1/0/X
|
||||
========= ===============
|
||||
|
||||
Legend:
|
||||
|
||||
* Qm/n: QTMR module m, channel n
|
||||
* Fm/n/l: FLEXPWM module m, submodule n, channel l. The pulse at a X channel
|
||||
is always aligned to the period start.
|
||||
|
||||
Pins without a PWM signal are not listed. A signal may be available at more
|
||||
than one Pin. FlexPWM pins may also be pure CPU pin, not assigned to a board
|
||||
signal. In that case the PWM output is disabled. The PWM channel of a submodule
|
||||
0 may still be used as synchronization source for other channels of the same
|
||||
module, unless used by another peripheral.
|
||||
|
||||
Submodule 0 pins for i.MX RT1011:
|
||||
|
||||
================== =======
|
||||
Pin Channel
|
||||
================== =======
|
||||
Pin.cpu.GPIO_01 B
|
||||
Pin.cpu.GPIO_02 A
|
||||
Pin.cpu.GPIO_AD_12 X
|
||||
Pin.cpu.GPIO_SD_01 B
|
||||
Pin.cpu.GPIO_SD_02 A
|
||||
================== =======
|
||||
|
||||
Submodule 0 pins for i.MX RT1021:
|
||||
|
||||
===================== ==================
|
||||
Pin Module & Channel
|
||||
===================== ==================
|
||||
Pin.cpu.GPIO_AD_B1_06 FLEXPWM1 Channel A
|
||||
Pin.cpu.GPIO_AD_B1_07 FLEXPWM1 Channel B
|
||||
Pin.cpu.GPIO_EMC_26 FLEXPWM1 Channel A
|
||||
Pin.cpu.GPIO_EMC_27 FLEXPWM1 Channel B
|
||||
Pin.cpu.GPIO_AD_B0_14 FLEXPWM2 Channel A
|
||||
Pin.cpu.GPIO_AD_B0_15 FLEXPWM2 Channel B
|
||||
Pin.cpu.GPIO_EMC_10 FLEXPWM2 Channel X
|
||||
Pin.cpu.GPIO_EMC_38 FLEXPWM2 Channel A
|
||||
Pin.cpu.GPIO_EMC_39 FLEXPWM2 Channel B
|
||||
===================== ==================
|
||||
|
||||
Submodule 0 pins for i.MX RT1052, i.MX RT1062 and i.MX RT1064:
|
||||
|
||||
===================== ==================
|
||||
Pin Module & Channel
|
||||
===================== ==================
|
||||
Pin.cpu.GPIO_AD_B0_02 FLEXPWM1 Channel X
|
||||
Pin.cpu.GPIO_EMC_23 FLEXPWM1 Channel A
|
||||
Pin.cpu.GPIO_EMC_24 FLEXPWM1 Channel B
|
||||
Pin.cpu.GPIO_SD_B0_00 FLEXPWM1 Channel A
|
||||
Pin.cpu.GPIO_SD_B0_01 FLEXPWM1 Channel B
|
||||
Pin.cpu.GPIO_B0_06 FLEXPWM2 Channel A
|
||||
Pin.cpu.GPIO_B0_07 FLEXPWM2 Channel B
|
||||
Pin.cpu.GPIO_EMC_06 FLEXPWM2 Channel A
|
||||
Pin.cpu.GPIO_EMC_07 FLEXPWM2 Channel B
|
||||
Pin.cpu.GPIO_EMC_29 FLEXPWM3 Channel A
|
||||
Pin.cpu.GPIO_EMC_30 FLEXPWM3 Channel B
|
||||
Pin.cpu.GPIO_AD_B1_08 FLEXPWM4 Channel A
|
||||
Pin.cpu.GPIO_EMC_00 FLEXPWM4 Channel A
|
||||
Pin.cpu.GPIO_EMC_01 FLEXPWM4 Channel B
|
||||
===================== ==================
|
||||
|
||||
Submodule 0 pins for i.MX RT1176
|
||||
|
||||
====================== ======================
|
||||
Pin Module & Channel
|
||||
====================== ======================
|
||||
Pin.cpu.GPIO_EMC_B1_00 FLEXPWM4 Channel A (*)
|
||||
Pin.cpu.GPIO_EMC_B1_01 FLEXPWM4 Channel B (*)
|
||||
Pin.cpu.GPIO_EMC_B1_06 FLEXPWM2 Channel A (*)
|
||||
Pin.cpu.GPIO_EMC_B1_07 FLEXPWM2 Channel B (*)
|
||||
Pin.cpu.GPIO_EMC_B1_23 FLEXPWM1 Channel A (*)
|
||||
Pin.cpu.GPIO_EMC_B1_24 FLEXPWM1 Channel B (*)
|
||||
Pin.cpu.GPIO_EMC_B1_29 FLEXPWM3 Channel A (*)
|
||||
Pin.cpu.GPIO_EMC_B1_30 FLEXPWM3 Channel B (*)
|
||||
Pin.cpu.GPIO_AD_00 FLEXPWM1 Channel A
|
||||
Pin.cpu.GPIO_AD_01 FLEXPWM1 Channel B
|
||||
Pin.cpu.GPIO_AD_24 FLEXPWM2 Channel A
|
||||
Pin.cpu.GPIO_AD_25 FLEXPWM2 Channel B
|
||||
====================== ======================
|
||||
|
||||
(*) Pin used for SDRAM
|
||||
|
||||
ADC (analog to digital conversion)
|
||||
----------------------------------
|
||||
|
||||
On the i.MXRT ADC functionality is available on Pins labeled 'Ann'.
|
||||
|
||||
Use the :ref:`machine.ADC <machine.ADC>` class::
|
||||
|
||||
from machine import ADC
|
||||
|
||||
adc = ADC(Pin(32)) # create ADC object on ADC pin
|
||||
adc.read_u16() # read value, 0-65536 across voltage range 0.0v - 3.3v
|
||||
|
||||
The resolution of the ADC is 12 bit with 10 to 11 bit accuracy, irrespective of the
|
||||
value returned by read_u16(). If you need a higher resolution or better accuracy, use
|
||||
an external ADC.
|
||||
|
||||
Software SPI bus
|
||||
----------------
|
||||
|
||||
Software SPI (using bit-banging) works on all pins, and is accessed via the
|
||||
:ref:`machine.SoftSPI <machine.SoftSPI>` class. ::
|
||||
|
||||
from machine import Pin, SoftSPI
|
||||
|
||||
# construct a SoftSPI bus on the given pins
|
||||
# polarity is the idle state of SCK
|
||||
# phase=0 means sample on the first edge of SCK, phase=1 means the second
|
||||
spi = SoftSPI(baudrate=100000, polarity=1, phase=0, sck=Pin(0), mosi=Pin(2), miso=Pin(4))
|
||||
|
||||
spi.init(baudrate=200000) # set the baudrate
|
||||
|
||||
spi.read(10) # read 10 bytes on MISO
|
||||
spi.read(10, 0xff) # read 10 bytes while outputting 0xff on MOSI
|
||||
|
||||
buf = bytearray(50) # create a buffer
|
||||
spi.readinto(buf) # read into the given buffer (reads 50 bytes in this case)
|
||||
spi.readinto(buf, 0xff) # read into the given buffer and output 0xff on MOSI
|
||||
|
||||
spi.write(b'12345') # write 5 bytes on MOSI
|
||||
|
||||
buf = bytearray(4) # create a buffer
|
||||
spi.write_readinto(b'1234', buf) # write to MOSI and read from MISO into the buffer
|
||||
spi.write_readinto(buf, buf) # write buf to MOSI and read MISO back into buf
|
||||
|
||||
The highest supported baud rate is 500000.
|
||||
|
||||
Hardware SPI bus
|
||||
----------------
|
||||
|
||||
There are up to four hardware SPI channels that allow faster transmission
|
||||
rates (up to 90Mhz). The SPI signals have fixed assignments to GPIO pins.
|
||||
It depends on the board design, which SPI's signals are exposed to the user, as
|
||||
detailed in the table below. The signal order in the table is: CS0, CS1, MOSI, MISO, CLK.
|
||||
|
||||
================= ========================= ======================= ===============
|
||||
Board / Pin SPI0 SPI1 SPI2
|
||||
================= ========================= ======================= ===============
|
||||
Teensy 4.0 10/-/11/12/13 0/-/26/1/27 -
|
||||
Teensy 4.1 10/37/11/12/13 0/-/26/1/27 -/29/50/54/49
|
||||
MIXMXRT1010-EVK D10/D7/D11/D12/D13 - -
|
||||
MIXMXRT1015-EVK D10/-/D11/D12/D13 - -
|
||||
MIXMXRT1020-EVK D10/-/D11/D12/D13 A3/D0/A5/A4/A0 -
|
||||
MIXMXRT1050-EVK D10/-/D11/D12/D13 (*) - -
|
||||
MIXMXRT1050-EVKB D10/-/D11/D12/D13 (*) - -
|
||||
MIXMXRT1060-EVK D10/-/D11/D12/D13 (*) - -
|
||||
MIXMXRT1064-EVK D10/-/D11/D12/D13 (*) - -
|
||||
MIXMXRT1170-EVK D10/-/D11/D12/D13 D28/-/D25/D24/D26 -/-/D14/D15/D24
|
||||
Olimex RT1010Py - CS0/-/SDO/SDI/SCK SDCARD with CS1
|
||||
Seeed ARCH MIX J4_12/-/J4_14/J4_13/J4_15 J3_09/J3_05/J3_08_J3_11
|
||||
================= ========================= ======================= ===============
|
||||
|
||||
Pins denoted with (*) are by default not wired at the board.
|
||||
|
||||
Hardware SPI is accessed via the :ref:`machine.SPI <machine.SPI>` class and
|
||||
has the same methods as software SPI above::
|
||||
|
||||
from machine import SPI
|
||||
|
||||
spi = SPI(0, 10000000)
|
||||
spi.write('Hello World')
|
||||
|
||||
Notes:
|
||||
|
||||
1. Even if the highest supported baud rate at the moment is 90 Mhz,
|
||||
setting a baud rate will not always result in exactly that
|
||||
frequency, especially at high baud rates.
|
||||
|
||||
2. Sending at 90 MHz is possible, but in the tests receiving
|
||||
only worked up to 60 MHz.
|
||||
|
||||
Software I2C bus
|
||||
----------------
|
||||
|
||||
Software I2C (using bit-banging) works on all output-capable pins, and is
|
||||
accessed via the :ref:`machine.SoftI2C <machine.SoftI2C>` class::
|
||||
|
||||
from machine import Pin, SoftI2C
|
||||
|
||||
i2c = SoftI2C(scl=Pin(5), sda=Pin(4), freq=100000)
|
||||
|
||||
i2c.scan() # scan for devices
|
||||
|
||||
i2c.readfrom(0x3a, 4) # read 4 bytes from device with address 0x3a
|
||||
i2c.writeto(0x3a, '12') # write '12' to device with address 0x3a
|
||||
|
||||
buf = bytearray(10) # create a buffer with 10 bytes
|
||||
i2c.writeto(0x3a, buf) # write the given buffer to the slave
|
||||
|
||||
The highest supported freq is 400000.
|
||||
|
||||
Hardware I2C bus
|
||||
----------------
|
||||
|
||||
There are up to four hardware I2C channels that allow faster transmission rates
|
||||
and support the full I2C protocol. The I2C signals have fixed assignments to GPIO pins.
|
||||
It depends on the board design, which I2C's signals are exposed to the user, as
|
||||
detailed in the table below. The signal order in the table is: SDA, SCL.
|
||||
|
||||
================= =========== =========== =========== ======= =======
|
||||
Board / Pin I2C 0 I2C 1 I2C 2 I2C 3 I2C 4
|
||||
================= =========== =========== =========== ======= =======
|
||||
Teensy 4.0 18/19 17/16 25/24 - -
|
||||
Teensy 4.1 18/19 17/16 25/24 - -
|
||||
MIXMXRT1010-EVK D14/D15 D0/D1 - - -
|
||||
MIXMXRT1015-EVK D14/D15 - - - -
|
||||
MIXMXRT1020-EVK D14/D15 A4/A5 D0/D1 - -
|
||||
MIXMXRT1050-EVK A4/A5 D1/D0 - - -
|
||||
MIXMXRT1050-EVKB A4/A5 D1/D0 - - -
|
||||
MIXMXRT1060-EVK A4/A5 D1/D0 - - -
|
||||
MIXMXRT1064-EVK A4/A5 D1/D0 - - -
|
||||
MIXMXRT1170-EVK D14/D15 D1/D0 A4/A5 D26/D25 D19/D18
|
||||
Olimex RT1010Py - SDA1/SCL1 SDA2/SCL2 - -
|
||||
Seeed ARCH MIX J3_17/J3_16 J4_06/J4_07 J5_05/J5_04 - -
|
||||
================= =========== =========== =========== ======= =======
|
||||
|
||||
Hardware I2C is accessed via the :ref:`machine.I2C <machine.I2C>` class and
|
||||
has the same methods as software SPI above::
|
||||
|
||||
from machine import I2C
|
||||
|
||||
i2c = I2C(0, 400_000)
|
||||
i2c.writeto(0x76, b"Hello World")
|
||||
|
||||
I2S bus
|
||||
-------
|
||||
|
||||
See :ref:`machine.I2S <machine.I2S>`. Example using a Teensy 4.1 board with a simple
|
||||
external Codec like UDA1334.::
|
||||
|
||||
from machine import I2S, Pin
|
||||
i2s = I2S(2, sck=Pin(26), ws=Pin(27), sd=Pin(7),
|
||||
mode=I2S.TX, bts=16,format=I2S.STEREO,
|
||||
rate=44100,ibuf=40000)
|
||||
i2s.write(buf) # write buffer of audio samples to I2S device
|
||||
|
||||
|
||||
Example for using I2S with a MIMXRT10xx_DEV board::
|
||||
|
||||
from machine import I2S, I2C, Pin
|
||||
import wm8960
|
||||
|
||||
i2c=I2C(0)
|
||||
|
||||
wm=wm8960.WM8960(i2c, sample_rate=SAMPLE_RATE_IN_HZ,
|
||||
adc_sync=wm8960.sync_dac,
|
||||
swap=wm8960.swap_input)
|
||||
|
||||
i2s = I2S(1, sck=Pin("SCK_TX"), ws=Pin("WS_TX"), sd=Pin("SD_RX"),
|
||||
mck=Pin("MCK),mode=I2S.RX, bts=16,format=I2S.MONO,
|
||||
rate=32000,ibuf=10000)
|
||||
i2s.readinto(buf) # fill buffer with audio samples from I2S device
|
||||
|
||||
In this example, the input channels are swapped in the WM8960 driver, since the
|
||||
on-board microphone is connected to the right channel, but mono audio is taken
|
||||
from the left channel. Note, that the sck and ws pins are connected to the TX
|
||||
signals of the I2S bus. That is intentional, since at the MW8960 codec these
|
||||
signals are shared for RX and TX.
|
||||
|
||||
Example using the Teensy audio shield::
|
||||
|
||||
from machine import I2C, I2S, Pin
|
||||
from sgtl5000 import CODEC
|
||||
i2s = I2S(1, sck=Pin(21), ws=Pin(20), sd=Pin(7), mck=Pin(23),
|
||||
mode=I2S.TX, bits=16,rate=44100,format=I2S.STEREO,
|
||||
ibuf=40000,
|
||||
)
|
||||
|
||||
# configure the SGTL5000 codec
|
||||
i2c = I2C(0, freq=400000)
|
||||
codec = CODEC(0x0A, i2c)
|
||||
codec.mute_dac(False)
|
||||
codec.dac_volume(0.9, 0.9)
|
||||
codec.headphone_select(0)
|
||||
codec.mute_headphone(False)
|
||||
codec.volume(0.7, 0.7)
|
||||
|
||||
i2s.write(buf) # write buffer of audio samples to I2S device
|
||||
|
||||
The SGTL5000 codec used by the Teensy Audio shield uses the RX signals for both
|
||||
RX and TX. Note that the codec is initialized after the I2S device. That is
|
||||
essential since MCK is needed for its I2C operation and is provided by the I2S
|
||||
controller.
|
||||
|
||||
MIMXRT boards may have 1 or 2 I2S buses available at the board connectors.
|
||||
On MIMXRT1010 devices the bus numbers are 1 and 3.
|
||||
|
||||
Pin assignments for a few MIMXRT boards:
|
||||
|
||||
=============== == ===== ======== ======= ======= ======== ======= =======
|
||||
Board ID MCK SCK_TX WS_TX SD_TX SCK_RX WS_RX SD_RX
|
||||
=============== == ===== ======== ======= ======= ======== ======= =======
|
||||
Teensy 4.0 1 23 26 27 7 21 20 8
|
||||
Teensy 4.0 2 33 4 3 2 - - 5
|
||||
Teensy 4.1 1 23 26 27 7 21 20 8
|
||||
Teensy 4.1 2 33 4 3 2 - - 5
|
||||
Seeed Arch MIX 1 J4_09 J4_14 J4_15 J14_13 J4_11 J4_10 J4_10
|
||||
Olimex RT1010Py 1 D8 D6 D7 D4 D1 D2 D3
|
||||
Olimex RT1010Py 3 - D10 D9 D11 - - -
|
||||
MIMXRT_DEV 1 "MCK" "SCK_TX" "WS_TX" "SD_TX" "SCK_RX" "WS_RX" "SD_RX"
|
||||
=============== == ===== ======== ======= ======= ======== ======= =======
|
||||
|
||||
Symbolic pin names are provided for the MIMXRT_10xx_DEV boards.
|
||||
These are provided for the other boards as well.
|
||||
|
||||
Real time clock (RTC)
|
||||
---------------------
|
||||
|
||||
See :ref:`machine.RTC <machine.RTC>`::
|
||||
|
||||
from machine import RTC
|
||||
|
||||
rtc = RTC()
|
||||
rtc.datetime((2017, 8, 23, 1, 12, 48, 0, 0)) # set a specific date and time
|
||||
rtc.datetime() # get date and time
|
||||
rtc.now() # return date and time in CPython format.
|
||||
|
||||
The i.MXRT MCU supports battery backup of the RTC. By connecting a battery of
|
||||
1.5-3.6V, time and date are maintained in the absence of the main power. The
|
||||
current drawn from the battery is ~20µA, which is rather high. A CR2032 coin
|
||||
cell will last for about one year.
|
||||
|
||||
SD card
|
||||
-------
|
||||
|
||||
See :ref:`machine.SDCard <machine.SDCard>`::
|
||||
|
||||
import machine, os
|
||||
|
||||
sd = machine.SDCard()
|
||||
fs = os.VfsFat(sd)
|
||||
os.mount(fs, "/sd") # mount
|
||||
os.listdir('/sd') # list directory contents
|
||||
os.umount('/sd') # eject
|
||||
|
||||
Note: The i.mx-rt 1011 and 1015 based boards do not support the ``machine.SDCard``
|
||||
class. For these, the SPI based driver ``sdcard.py`` from the MicroPython drivers
|
||||
can be used. When using it, you have to overdrive the CS pin of the SPI hardware
|
||||
module. Example::
|
||||
|
||||
import os, sdcard, machine
|
||||
|
||||
cs_pin = "D10"
|
||||
spi = machine.SPI(0) # SPI0 with cs at Pin "D10" used for SDCARD
|
||||
cs = machine.Pin(cs_pin, machine.Pin.OUT, value=1)
|
||||
sd = sdcard.SDCard(spi, cs)
|
||||
vfs = os.VfsFat(sd)
|
||||
os.mount(vfs, "/sdcard")
|
||||
|
||||
OneWire driver
|
||||
--------------
|
||||
|
||||
The OneWire driver is implemented in software and works on all pins::
|
||||
|
||||
from machine import Pin
|
||||
import onewire
|
||||
|
||||
ow = onewire.OneWire(Pin(12)) # create a OneWire bus on GPIO12
|
||||
ow.scan() # return a list of devices on the bus
|
||||
ow.reset() # reset the bus
|
||||
ow.readbyte() # read a byte
|
||||
ow.writebyte(0x12) # write a byte on the bus
|
||||
ow.write('123') # write bytes on the bus
|
||||
ow.select_rom(b'12345678') # select a specific device by its ROM code
|
||||
|
||||
There is a specific driver for DS18S20 and DS18B20 devices::
|
||||
|
||||
import time, ds18x20
|
||||
ds = ds18x20.DS18X20(ow)
|
||||
roms = ds.scan()
|
||||
ds.convert_temp()
|
||||
time.sleep_ms(750)
|
||||
for rom in roms:
|
||||
print(ds.read_temp(rom))
|
||||
|
||||
Be sure to put a 4.7k pull-up resistor on the data line. Note that
|
||||
the ``convert_temp()`` method must be called each time you want to
|
||||
sample the temperature.
|
||||
|
||||
DHT driver
|
||||
----------
|
||||
|
||||
The DHT driver is implemented in software and works on all pins::
|
||||
|
||||
import dht
|
||||
import machine
|
||||
|
||||
d = dht.DHT11(machine.Pin(4))
|
||||
d.measure()
|
||||
d.temperature() # eg. 23 (°C)
|
||||
d.humidity() # eg. 41 (% RH)
|
||||
|
||||
d = dht.DHT22(machine.Pin(4))
|
||||
d.measure()
|
||||
d.temperature() # eg. 23.6 (°C)
|
||||
d.humidity() # eg. 41.3 (% RH)
|
||||
|
||||
Be sure to have a 4.7k pull-up resistor on the data line. Some
|
||||
DHT modules may already have one.
|
||||
|
||||
Ethernet driver
|
||||
---------------
|
||||
|
||||
All MIMXRT boards except the MIMXRT1011 based boards and Teensy 4.0 support
|
||||
Ethernet. Example usage::
|
||||
|
||||
import network
|
||||
|
||||
lan = network.LAN(0)
|
||||
lan.active(True)
|
||||
|
||||
If there is a DHCP server in the LAN, the IP address is supplied by that server.
|
||||
Otherwise, the IP address can be set with lan.ifconfig(). The default address
|
||||
is 192.168.0.1.
|
||||
|
||||
Teensy 4.1 does not have an Ethernet jack on the board, but PJRC offers an
|
||||
adapter for self-assembly. The Seeed ARCH MIX board has no PHY hardware on the
|
||||
board, however you can attach external PHY interfaces. By default, the firmware
|
||||
for Seeed Arch Mix uses the driver for a LAN8720 PHY. The MIMXRT1170_EVK is
|
||||
equipped with two Ethernet ports, which are addressed as LAN(0) for the 100M
|
||||
port and LAN(1) for the 1G port.
|
||||
|
||||
For details of the network interface refer to the class :ref:`network.LAN <network.LAN>`.
|
||||
|
||||
Transferring files
|
||||
------------------
|
||||
|
||||
Files can be transferred to the i.MXRT devices for instance with the ``mpremote``
|
||||
tool or using an SD card. If Ethernet is available, you can also use ftp.
|
||||
See the MicroPython forum for the FTP server or other community-supported
|
||||
alternatives to transfer files to an i.MXRT board, like rshell or Thonny.
|
||||
|
|
@ -0,0 +1,125 @@
|
|||
.. _mimxrt_intro:
|
||||
|
||||
Getting started with MicroPython on the i.MXRT
|
||||
==============================================
|
||||
|
||||
Using MicroPython is a great way to get the most of your i.MXRT board. And
|
||||
vice versa, the i.MXRT chip is a great platform for using MicroPython. This
|
||||
tutorial will guide you through setting up MicroPython, getting a prompt, using
|
||||
the hardware peripherals, and controlling some external components.
|
||||
|
||||
Let's get started!
|
||||
|
||||
Requirements
|
||||
------------
|
||||
|
||||
The first thing you need is a board with an i.MXRT chip. The MicroPython
|
||||
software supports the i.MXRT chip itself and any board should work. The main
|
||||
characteristic of a board is how the GPIO pins are connected to the outside
|
||||
world, and whether it includes a built-in USB-serial converter to make the
|
||||
UART available to your PC.
|
||||
|
||||
Names of pins will be given in this tutorial using the chip names (eg GPIO2)
|
||||
and it should be straightforward to find which pin this corresponds to on your
|
||||
particular board.
|
||||
|
||||
Powering the board
|
||||
------------------
|
||||
|
||||
If your board has a USB connector on it then most likely it is powered through
|
||||
this when connected to your PC. Otherwise you will need to power it directly.
|
||||
Please refer to the documentation for your board for further details.
|
||||
|
||||
Getting the firmware
|
||||
--------------------
|
||||
|
||||
Firmware versions are provided at the
|
||||
`MicroPython download page <https://micropython.org/download/?port=mimxrt>`_.
|
||||
You can download the most recent MicroPython firmware .hex or .bin file to load
|
||||
onto your i.MXRT device. From that download page you have two main choices:
|
||||
|
||||
* stable firmware builds
|
||||
* daily firmware builds
|
||||
|
||||
If you are just starting with MicroPython, the best bet is to go for the stable
|
||||
firmware builds. If you are an advanced, experienced MicroPython i.MXRT user
|
||||
who would like to follow development closely and help with testing new
|
||||
features, there are daily builds.
|
||||
|
||||
Deploying the firmware
|
||||
----------------------
|
||||
|
||||
Once you have the MicroPython firmware you need to load it onto your
|
||||
i.MXRT device. The exact procedure for these steps is highly dependent
|
||||
on the particular board and you will need to refer to its documentation
|
||||
for details.
|
||||
|
||||
Teensy 4.0 and 4.1
|
||||
~~~~~~~~~~~~~~~~~~
|
||||
|
||||
For Teensy 4.0 and 4.1 you have to use the built-in loader together with the PC
|
||||
loader provided by PJRC. The built-in loader will be activated by pushing the
|
||||
button on the board. Then you can upload the firmware with the command::
|
||||
|
||||
teensy_loader_cli --mcu=imxrt1062 -v -w firmware.hex
|
||||
|
||||
IMXRT10xx-EVK boards
|
||||
~~~~~~~~~~~~~~~~~~~~
|
||||
|
||||
The IMXRT10xx-EVK boards have a second USB port connected to a support MCU.
|
||||
Connecting that USB port to your PC will register a disk drive with the name of
|
||||
the board. Just copy the firmware.bin file to this drive, and that will start
|
||||
the flashing procedure. You will know that the flash was complete, if that
|
||||
drive disappears and reappears. If you decided to install the very useful
|
||||
Segger open-SDA firmware on that sidekick MCU, then you have to use the debugger
|
||||
software to upload the i.MXRT firmware.
|
||||
|
||||
Seed ARCH MIX board
|
||||
~~~~~~~~~~~~~~~~~~~
|
||||
|
||||
Firmware upload to the Seed ARCH MIX board is less convenient. The vendor
|
||||
suggests using J-Link as a method and tool. For that, follow the instructions
|
||||
given by Seed in their Wiki at
|
||||
https://wiki.seeedstudio.com/Arch_Mix/#flashing-arduino-bootloader-to-arch-mix.
|
||||
You will need a J-Link debug probe and software. You may find Segger JLink edu
|
||||
or Segger JLink edu mini convenient. As a matching loader you can use
|
||||
JFlashLite. The target address for loading is 0x60000000.
|
||||
|
||||
The MIMXRT family also support a serial upload method. The software for serial
|
||||
upload is provided by NXP. The steps to use it are:
|
||||
|
||||
- Connect J3, Pin 19 to 3.3V (GPIO_AD_B0_05).
|
||||
- Change the DIP-Switch settings from off-off-on-off to off-off-off-on
|
||||
- Push Reset
|
||||
- Run the upload with: ./FLASH.sh <firmware_image_file name>
|
||||
- Once the upload has finished, set the DIP-switch back to off-off-on-off.
|
||||
- Remove the Jumper to J3, Pin19 and push reset
|
||||
|
||||
To avoid running the Flash loader as superuser, you can copy the provided udev-rules
|
||||
script to /etc/udev/rules.d/. FLASH.sh calls two binaries, blhost and sdphost,
|
||||
which are provided by NXP under the BSD-3-Clause License. A version of these
|
||||
binaries and the script can be downloaded at
|
||||
https://github.com/robert-hh/Shared-Stuff/blob/master/mimxrt_serial_downloader.zip.
|
||||
|
||||
Serial downloading can be used for the NXP MIMXRT boards as well. But the built-in loader
|
||||
is much more convenient to use.
|
||||
|
||||
Serial prompt
|
||||
-------------
|
||||
|
||||
Once you have the firmware on the device you can access the REPL (Python prompt)
|
||||
over USB.
|
||||
|
||||
From there you can follow the i.MXRT tutorial.
|
||||
|
||||
Troubleshooting installation problems
|
||||
-------------------------------------
|
||||
|
||||
If you experience problems during flashing or with running firmware immediately
|
||||
after it, here are some troubleshooting recommendations:
|
||||
|
||||
* Be aware of and try to exclude hardware problems. There are two common
|
||||
problems: bad power source quality, and worn-out/defective Flash ROM.
|
||||
Speaking of power source, not just raw amperage is important, but also low
|
||||
ripple and noise/EMI in general. The most reliable and convenient power
|
||||
source is a USB port.
|
||||
|
|
@ -62,6 +62,10 @@
|
|||
<a class="biglink" href="{{ pathto("rp2/quickref") }}">Quick reference for the Raspberry Pi RP2xxx</a><br/>
|
||||
<span class="linkdescr">pinout for rp2xxx-based boards, snippets of useful code, and a tutorial</span>
|
||||
</p>
|
||||
<p class="biglink">
|
||||
<a class="biglink" href="{{ pathto("mimxrt/quickref") }}">Quick reference for the NXP i.MXRT 10xx</a><br/>
|
||||
<span class="linkdescr">general introduction, snippets of useful code, and a tutorial</span>
|
||||
</p>
|
||||
<p class="biglink">
|
||||
<a class="biglink" href="{{ pathto("wipy/quickref") }}">Quick reference for the WiPy/CC3200</a><br/>
|
||||
<span class="linkdescr">pinout for the WiPy/CC3200, snippets of useful code, and a tutorial</span>
|
||||
|
|
|
|||
Ładowanie…
Reference in New Issue