BSII output hardware suggestions needed

DonSlepian

I am working on a footpedal project that may be an aid to disabled people. I have some programming/electronics background but I am new to the Basic Stamp world. I have a BSII with prototyping board and I'm working with the Scott Edwards book on Programming and Customizing the Basic Stamp Computer. I would like to have the BSII read a value from an ADC0831 ADC and close one of 64 CMOS analog switches (I'm using the old CD4016) in response. I can use the ADC programming code from the Time/Temperature display project. I'm looking for help on the output hardware. I have 8 output pins available. The closest chip I've found that could interface between the Basic Stamp II outputs and my CD4016 analog switches is the CD45154BC 4-to-16 line decoder. I could try using 4 of those, but is there a more elegant solution? I suspect 6 BSII output pins connecting to a collection of simple logic gates would do it, but I can't picture the circuit. Thank you so much for any suggestions!

Don Slepian, Don@DonSlepian.com

allanlane5

Typically you would use a 74HCT595 Serial to Parallel converter chip to do this sort of thing. This would use 3 pins of the BS2 to send data using the 'SHIFTOUT' command to the '595's -- and it would support any number of '595's.

So get 8 '595's, determine what the CD4016's want to be sent to control them, and do a SHIFTOUT of 8-bytes from the BS2 to the '595's. Send the parallel outputs of the '595's to the CD4016's, and you should be good to go.

DonSlepian

Thank you very much! I'll give that approach a try. I appreciate your help.