Initial commit

BM/softuart.py

@@ -0,0 +1,56 @@
+from machine import Pin
+from rp2 import PIO, StateMachine, asm_pio
+
+
+## ASM
+@asm_pio(autopush=True, push_thresh=8, in_shiftdir=PIO.SHIFT_RIGHT, fifo_join=PIO.JOIN_RX)
+def uart_rx_mini():
+    wait(0, pin, 0)
+    set(x, 7)                 [10]
+    label("bitloop")
+    in_(pins, 1)
+    jmp(x_dec, "bitloop")     [6]
+
+
+@asm_pio(sideset_init=PIO.OUT_HIGH, out_init=PIO.OUT_HIGH, out_shiftdir=PIO.SHIFT_RIGHT)
+def uart_tx():
+    pull()
+    set(x, 7)  .side(0)       [7]
+    label("bitloop")
+    out(pins, 1)              [6]
+    jmp(x_dec, "bitloop")
+    nop()      .side(1)       [6]
+        
+
+
+class UART:
+
+    def __init__(self, rx, tx, baudrate, id):
+        self.UART_BAUD = baudrate
+        self.PIO_RX_PIN = Pin(rx, Pin.IN, Pin.PULL_UP)
+        self.PIO_TX_PIN = Pin(tx, Pin.OUT, value=1)
+        self.smrx = StateMachine(id, uart_rx_mini, freq=8*self.UART_BAUD, in_base=self.PIO_RX_PIN, jmp_pin=self.PIO_RX_PIN)
+        self.smrx.active(1)
+        self.smtx = StateMachine(id + 1, uart_tx, freq=8*self.UART_BAUD, sideset_base=self.PIO_TX_PIN, out_base=self.PIO_TX_PIN)
+        self.smtx.active(1)
+        
+    def deinit(self):
+        self.smrx.active(0)
+        self.smtx.active(0)
+        
+    def write(self,s):
+        #self.smtx.put(bytes(s))
+        self.smtx.put(s)
+        return len(s)
+
+    def read(self):
+        z = []
+
+        for i in range(100):
+            buflen = self.smrx.rx_fifo()
+
+            if buflen:
+                for c in range(buflen): 
+                    z.append(self.smrx.get() >> 24)
+
+        return bytes(z)