MCP3201 Programming Log - Part 2 (SPI loopback test v08)

MCP3201 Programming Log - Part 2 (SPI loopback test v08)

# spitestv08_2020jan0102.py tlfong01 2021jan01hkt1224 ***

# *** Configuration Description ***

# Rpi4B Thonny Python 3.7.3 (/usr/bin/python3)

# pi@raspberrypi:~ $ date Fri 01 Jan 2021 12:17:54 PM HKT

# pi@raspberrypi:~ $ uname -a Linux raspberrypi 5.4.79-v7l+ #1373 SMP Mon Nov 23 13:27:40 GMT 2020 armv7l GNU/Linux

# *** Test Description ***

# Test 1   - loopBackTest()   - SPI port send and receive one byte.

#   Function - Send one byte to MSOI and read it back from MISO. 

#   Setup    - Connet MOSI pin to MISO pin to form a loop.

# Test 2   - repeatSendByte() - SPI port repeatedly send out single bytes.  

#   Function - Repeat many times sending a byte, pause after each byte.

# *** Import ***

from datetime import datetime

from time import sleep

import spidev

# **　SPI Setup/Config ***

spiPort0 = spidev.SpiDev()

spiPort0.open(0,0)

spiPort0.max_speed_hz = 100000

#*** System Functions ***

timeNowLong  = str(datetime.now())

timeNowShort = str(datetime.now())[0:16]

# *** SPI System Functions ***

def spiSendRecvOneByte(spiPort, sendByte):

    sendByteArray = [sendByte]

    recvByteArray = spiPort.xfer(sendByteArray)    

    return recvByteArray

def loopBackOneByte(spiPort, sendByte):

    recvByteArray     = spiSendRecvOneByte(spiPort, sendByte)

    recvByte          = recvByteArray[0]

    print('  Begin testLoopbackOneByte(),....')

    #print('')

    print('    Note 1    =  Connect SPI MOSI pin to MISO pin to loop back!')

    print('    Note 2    =  Loopback results below:')

    print('    sendByte  = ', hex(sendByte))

    print('    recvByte  = ', hex(recvByte))

    #print('')

    print('  End   testLoopbackOneByte(),....')

    return

def repeatSendOneByte(spiPort, sendByte, pauseTimeBetweenBytes, repeatCount):

    print('\nBegin repeatSendByte(),....')

    for i in range(repeatCount):

        spiSendRecvOneByte(spiPort, sendByte)

        sleep(pauseTimeBetweenBytes)

    print('End   repeatSendByte().')

    return

# *** SPI Test Functions ***

def testRepeatSendOneByte():

    repeatSendOneByte(spiPort0, 0x5b, 0.0001, 20000000)

    return

def testLoopbackOneByte():

    loopBackOneByte(spiPort0, 0x5b)

    return

# *** Init/Main Function ***

def init():

    pass

    return

def main():

    #testRepeatSendOneByte()

    #testLoopbackOneByte()

    print('Begin main(), ... - tlfong01', timeNowShort)

    loopBackOneByte(spiPort0, 0x5b)

    print('End   main().')

    return

# *** Main()

if __name__ == '__main__':

    main()

# *** End of Program ***

# *** Sample Output ***

# Smple output tlfong 01 2019apr07hkt2047

'''

>>> %Run sptestv08_2021jan0103.py

Begin main(), ... - tlfong01 2021-01-01 12:37

  Begin testLoopbackOneByte(),....

    Note 1    =  Connect SPI MOSI pin to MISO pin to loop back!

    Note 2    =  Loopback results below:

    sendByte  =  0x5b

    recvByte  =  0x5b

  End   testLoopbackOneByte(),....

End   main().

>>> 

'''

# *** End of Sample Output ***