Hi Guys
While recently testing some of my own expanders , I decided to browse the net looking for an opto isolator boards to connect to my expanders and came across a site
Which made input expanders with onboard opto isolation and also output expanders with relays onboard…..they make expanders using the PCF8574 chip which is used for port C and also the ports on Homevision,s Multifunction board,s and also expanders using the PCF8574A chip which I use on my expander….

I purchased some of the input boards for both chips and a relay board which uses the PCF8574A chip….. I modified one of their 5way cables to interface with the homevision ribbon cable
And have them working on my bench……I was able to mimic the multifunction ports D + G using the PCF8574 Board which was great….and also I mimicked the ports which were reserved for future use……So if your running out of inputs / outputs you should give these boards a try…The prices are in US dollars and I believe the company is in thailand…. I received my boards within a week of ordering…