micropython-samples/uasyncio_iostream/tests/iotest5.py

107 wiersze
3.4 KiB
Python

# iotest5.py Test PR #3836.
# User class write() performs unbuffered writing.
# Read is also unbuffered.
# This test was to demonstrate the original issue.
# With modified moduselect.c and uasyncio.__init__.py the test now passes.
# iotest4.test() uses separate read and write objects.
# iotest4.test(False) uses a common object (failed without the mod).
import io, pyb
import uasyncio as asyncio
import micropython
micropython.alloc_emergency_exception_buf(100)
MP_STREAM_POLL_RD = const(1)
MP_STREAM_POLL_WR = const(4)
MP_STREAM_POLL = const(3)
MP_STREAM_ERROR = const(-1)
def printbuf(this_io):
for ch in this_io.wbuf[:this_io.wprint_len]:
print(chr(ch), end='')
class MyIO(io.IOBase):
def __init__(self, read=False, write=False):
self.ready_rd = False # Read and write not ready
self.rbuf = b'ready\n' # Read buffer
self.ridx = 0
pyb.Timer(4, freq = 5, callback = self.do_input)
self.wch = b''
self.wbuf = bytearray(100) # Write buffer
self.wprint_len = 0
self.widx = 0
pyb.Timer(5, freq = 10, callback = self.do_output)
# Read callback: emulate asynchronous input from hardware.
# Typically would put bytes into a ring buffer and set .ready_rd.
def do_input(self, t):
self.ready_rd = True # Data is ready to read
# Write timer callback. Emulate hardware: if there's data in the buffer
# write some or all of it
def do_output(self, t):
if self.wch:
self.wbuf[self.widx] = self.wch
self.widx += 1
if self.wch == ord('\n'):
self.wprint_len = self.widx # Save for schedule
micropython.schedule(printbuf, self)
self.widx = 0
self.wch = b''
def ioctl(self, req, arg): # see ports/stm32/uart.c
ret = MP_STREAM_ERROR
if req == MP_STREAM_POLL:
ret = 0
if arg & MP_STREAM_POLL_RD:
if self.ready_rd:
ret |= MP_STREAM_POLL_RD
if arg & MP_STREAM_POLL_WR:
if not self.wch:
ret |= MP_STREAM_POLL_WR # Ready if no char pending
return ret
# Test of device that produces one character at a time
def readline(self):
self.ready_rd = False # Cleared by timer cb do_input
ch = self.rbuf[self.ridx]
if ch == ord('\n'):
self.ridx = 0
else:
self.ridx += 1
return chr(ch)
# Emulate unbuffered hardware which writes one character: uasyncio waits
# until hardware is ready for the next. Hardware ready is emulated by write
# timer callback.
def write(self, buf, off, sz):
self.wch = buf[off] # Hardware starts to write a char
return 1 # 1 byte written. uasyncio waits on ioctl write ready
async def receiver(myior):
sreader = asyncio.StreamReader(myior)
while True:
res = await sreader.readline()
print('Received', res)
async def sender(myiow):
swriter = asyncio.StreamWriter(myiow, {})
await asyncio.sleep(5)
count = 0
while True:
count += 1
tosend = 'Wrote Hello MyIO {}\n'.format(count)
await swriter.awrite(tosend.encode('UTF8'))
await asyncio.sleep(2)
myior = MyIO()
myiow = myior
loop = asyncio.get_event_loop()
loop.create_task(receiver(myior))
loop.create_task(sender(myiow))
loop.run_forever()