Beagle Bone Black: i2cget working with k8000

After implementing this circuit, where FEZ is replace with BBB ic2get results are valid.

Here is what it looks like (orange wire and above is from an unrelated 1-wire circuit):

K8000 reference is here:

Here are the results of the first chip at address 0x38.

i2cget -y 2 0x38

0x8f

0x39 works as well, but is currently configured to have the 4 most significant bits as outputs.

This python script also works to control the IO on the K8000 (which has the PCF8574A chips) via the BBB:

Here is my modified script to turn RED and GRN LEDS on and off:

#!/usr/bin/python

# access K8000 via BBB i2c

from smbus import SMBus

from itertools import cycle

from time import sleep

LIGHTSOFF = 0xff

LIGHTSON = 0x9f

REDON = 0Xbf

GRNON = 0Xdf

LIGHTS = (LIGHTSON, REDON, GRNON, LIGHTSOFF)

bus = SMBus(2) # bus 2 is wired to talk with k8000

for OUTPUT in cycle(LIGHTS):

bus.write_byte(0x39, OUTPUT)

sleep(0.1)

Beagle Bone Black