X-Git-Url: https://git.ayoreis.com/Adafruit_Blinka-hackapet.git/blobdiff_plain/150f00e4e6bc32ada132fbb8529700afaa4fe4a0..28f9b9ec689e55a09366cc6bf8d03f170bec6db8:/src/adafruit_blinka/microcontroller/ft232h/spi.py diff --git a/src/adafruit_blinka/microcontroller/ft232h/spi.py b/src/adafruit_blinka/microcontroller/ft232h/spi.py index 9ae5751..a260e72 100644 --- a/src/adafruit_blinka/microcontroller/ft232h/spi.py +++ b/src/adafruit_blinka/microcontroller/ft232h/spi.py @@ -3,55 +3,52 @@ from adafruit_blinka.microcontroller.ft232h.pin import Pin class SPI: MSB = 0 - baudrate = 100000 - mode = 0 - bits = 8 - def __init__(self): - # change GPIO controller to SPI from pyftdi.spi import SpiController self._spi = SpiController(cs_count=1) self._spi.configure('ftdi:///1') + self._port = self._spi.get_port(0) + self._port.set_frequency(100000) + self._port._cpol = 0 + self._port._cpha = 0 + # Change GPIO controller to SPI Pin.ft232h_gpio = self._spi.get_gpio() def init(self, baudrate=100000, polarity=0, phase=0, bits=8, firstbit=MSB, sck=None, mosi=None, miso=None): - self.cs = 0 - self.freq = baudrate - if polarity == 0 and phase == 0: - self.mode = 0 - elif polarity == 0 and phase == 1: - self.mode = 1 - elif polarity == 1 and phase == 0: - raise ValueError("SPI mode 2 is not supported.") - elif polarity == 1 and phase == 1: - self.mode = 3 - else: - raise ValueError("Unknown SPI mode.") + self._port.set_frequency(baudrate) + # FTDI device can only support mode 0 and mode 2 + # due to the limitation of MPSSE engine. + # This means CPHA must = 0 + self._port._cpol = polarity + if phase != 0: + raise ValueError("Only SPI phase 0 is supported by FT232H.") + self._port._cpha = phase + + @property + def frequency(self): + return self._port.frequency def write(self, buf, start=0, end=None): end = end if end else len(buf) - port = self._spi.get_port(self.cs, self.freq, self.mode) chunks, rest = divmod(end - start, self._spi.PAYLOAD_MAX_LENGTH) for i in range(chunks): chunk_start = start + i * self._spi.PAYLOAD_MAX_LENGTH chunk_end = chunk_start + self._spi.PAYLOAD_MAX_LENGTH - port.write(buf[chunk_start:chunk_end]) + self._port.write(buf[chunk_start:chunk_end]) if rest: - port.write(buf[-1*rest:]) + self._port.write(buf[-1*rest:]) def readinto(self, buf, start=0, end=None, write_value=0): end = end if end else len(buf) - port = self._spi.get_port(self.cs, self.freq, self.mode) - result = port.read(end-start) + result = self._port.read(end-start) for i, b in enumerate(result): buf[start+i] = b def write_readinto(self, buffer_out, buffer_in, out_start=0, out_end=None, in_start=0, in_end=None): out_end = out_end if out_end else len(buffer_out) in_end = in_end if in_end else len(buffer_in) - port = self._spi.get_port(self.cs, self.freq, self.mode) - result = port.exchange(buffer_out[out_start:out_end], - in_end-in_start, duplex=True) + result = self._port.exchange(buffer_out[out_start:out_end], + in_end-in_start, duplex=True) for i, b in enumerate(result): buffer_in[in_start+i] = b