# -*- coding: utf-8 -*-
# Copyright (c) 2017 RS Components Ltd
# SPDX-License-Identifier: MIT License
"""
Interface for PmodAD1 module (AD7476A).
.. note::
Only a single channel (A1) is supported at present due to the way that SPI is configured.
"""
import spidev
CAP = 'SPI'
PHY = '1x6'
[docs]class PmodAD1:
def __init__(self, DSPMod6):
self.port = DSPMod6
self.cs = self.port.pin1
self.d0 = self.port.pin2
self.d1 = self.port.pin3 #miso
self.clk = self.port.pin4
self.spi = spidev.SpiDev()
self.__startSPI()
def __startSPI(self):
if self.cs == 7: #CE1
self.spi.open(0,1)
elif self.cs == 8: #CE0
self.spi.open(0,0)
else:
#throw exception here
return
self.spi.max_speed_hz = 100000
self.spi.mode = 0b00
def __stopSPI(self):
self.spi.close()
def __spiRead16(self):
resp = self.spi.xfer2([0x00, 0x00])
w = resp[0]
w <<= 8
w |= resp[1]
return w
[docs] def readA1(self):
return self.__spiRead16()
[docs] def readA1Volts(self):
w = self.__spiRead16()
refV = 3.3
lsb = refV/4096
volts= w*lsb
return volts
[docs] def cleanup(self):
self.__stopSPI()