Make use of a single ServoTrigger for multiple Servo PIOs

pio/pio_servo/pio_servo.py

@@ -6,7 +6,8 @@ from time import sleep
 
 @asm_pio()
 def servo_trigger():
-    irq(clear, rel(1))    # Clear next relative ISR, allows servo code to run again
+    irq(clear, 4)    # Clear next relative ISR, allows servo code to run again
+    irq(4)
     mov(y, x)             # Counter is stored in x, copy to y for use
     label("base")
     jmp(y_dec, "base")    # wait for programmed time
@@ -15,7 +16,7 @@ def servo_trigger():
 def servo_prog():
     wrap_target()
     
-    irq(block, rel(0)) .side(0) # Wait here for IRQ to be released by trigger SM
+    wait(0, "irq", 4) .side(0) # Wait here for IRQ to be released by trigger SM
     
     pull(noblock)        # pull new pulse length into fifo (pull fifo into OSR, if empty fifo copies X->OSR)
     mov(x, osr)          # Keep most recent pull data stashed in X, for recycling by noblock (later)
@@ -41,7 +42,7 @@ class ServoTrigger:
         
         trig_frq = 10_000 #Hz
         sm_trig = StateMachine(sm_idx, servo_trigger, freq=trig_frq)
-        trig_ctr = (trig_frq // 1000 * trig_target) - 3 # 3 instructions to have perfect 20ms on IRQ
+        trig_ctr = (trig_frq // 1000 * trig_target) - 4 # 3 instructions to have perfect 20ms on IRQ
 
         sm_trig.put(trig_ctr)
         sm_trig.exec("pull()")
@@ -57,11 +58,11 @@ class Servo:
     Preload the ISR with the base duration (fixed pulse length for position 0°)
     Send position data via FIFO into the OSR (variable pulse length for 0°..max)
     '''
-    def __init__(self, sm_idx, pin):
+    def __init__(self, sm_idx, pin, min_pulse, max_pulse):
         self.baseFrq = 1_000_000 # 1MHz = 1us clock base
         
-        self.base_pulse = 1000 # us, base width of pulse
-        self.free_pulse = 1000 # us, max. additional length set by percent
+        self.base_pulse = min_pulse             # us, base width of pulse
+        self.free_pulse = max_pulse - min_pulse # us, max. additional length set by percent
         
         self.sm = StateMachine(sm_idx, servo_prog, freq=self.baseFrq, sideset_base=Pin(pin))
 
@@ -76,13 +77,15 @@ class Servo:
         self.sm.put(int(self.free_pulse*n))
 
 # Trigger needs to be the sm before the servo, so the IRQs set by rel(n) match
-trig = Servo_Trigger(0)
-s = Servo(1, 16) # phys IO on pin 16
-
-trig2 = Servo_Trigger(2)
-s2 = Servo(3, 25) # Builtin LED
+trig = ServoTrigger(0)
+s = Servo(1, 16, 1000, 2000) # phys IO on pin 16, with 1ms..2ms pulse width
+s2 = Servo(3, 17, 1000, 2000) # phys IO on pin 16, with 1ms..2ms pulse width
 
 while True:
     for p in range(10+1):
-        s.pos(p/10)
-        sleep(0.5)
+        p = p/10 # Scale 0..10 to 0..1
+        
+        s.pos(p)
+        s2.pos(1-p)
+        
+        sleep(0.5)