[solved] Drive 4-Channel SPDT Relay via I2C/smbus2 python

I’m hitting the complete lock up problem when trying to use the 4-Channel SPDP Relay. Happened upon this post. I’ll give my feedback when done.

First, that tale will make a bit more sense if you reverse the registers

       4   3   2   1
       ---------------
0x00:  OFF OFF OFF OFF
0x01:  OFF OFF OFF ON 
0x02:  OFF OFF ON   OFF
0x03:  OFF OFF ON   ON 
0x04:  OFF ON OFF OFF
0x05:  OFF ON OFF ON 
0x06:  OFF ON ON OFF
0x07:  OFF ON ON OFF ON 
0x08:  ON OFF OFF OFF
0x09:  ON OFF OFF ON 
0x0a:  ON OFF ON OFF
0x0b:  ON OFF ON ON 
0x0c:  ON ON OFF OFF
0x0d:  ON ON OFF ON 
0x0e:  ON ON ON OFF
0x0f:  ON ON ON ON 

Thanks for the hints.