DM: added write_readinto to bitbangio

[deanm1278]

add write_readinto support to bitbangio #472

note that in the current master branch bitbangio module is not compiled in by default and will have to be added into the makefile

code sample:

import bitbangio
import board

spi = bitbangio.SPI(board.D10, board.D6, board.D9)

while not spi.try_lock():
    pass

a = bytearray(2)
spi.write_readinto(bytes([9, 88]), a)

#if mosi and miso are connected this should print 9, 88
for b in a:
    print(b)

[tannewt]

Two minor things

[tannewt]

Is this a tab instead of spaces? (I realize its pedantic.) Could please set your editor up to do 4 spaces when tab is hit?

[tannewt]

Please change the params to buffer_in, buffer_out to match the comment below.

[deanm1278]

ok updated @tannewt

[dhalbert]

It looks like there are still tabs in the two SPI.c files. Could you untabify them in Atmel Studio or maybe from the command line? http://mlawire.blogspot.com/2009/07/convert-tabs-to-spaces.html

[deanm1278]

@dhalbert ok updated

[tannewt]

Looks good! Thank you thank you!