spi in_base pin_sck to pin_miso.

pio/pio_spi.py

@@ -27,7 +27,7 @@ class PIOSPI:
 
     def __init__(self, sm_id, pin_mosi, pin_miso, pin_sck, cpha=False, cpol=False, freq=1000000):
         assert(not(cpol or cpha))
-        self._sm = rp2.StateMachine(sm_id, spi_cpha0, freq=4*freq, sideset_base=Pin(pin_sck), out_base=Pin(pin_mosi), in_base=Pin(pin_sck))
+        self._sm = rp2.StateMachine(sm_id, spi_cpha0, freq=4*freq, sideset_base=Pin(pin_sck), out_base=Pin(pin_mosi), in_base=Pin(pin_miso))
         self._sm.active(1)
 
     # Note this code will die spectacularly cause we're not draining the RX FIFO