Analog pin multiplexing using an AMUXBUS | Cypress Semiconductor
Analog pin multiplexing using an AMUXBUS
As a developer I'm new to PSOC so I've got a small but somewhat complex mixed signal project I'm trying to re-implement using PSOC 4 to get the hang of it.
Both the SARADC and the SARMUX buses are used, but I also need to implement an analog mux between a few pins to switch external passive components through the signal path.
I've tried a bunch of things over a couple of hours, but I simply cannot get PSOC Creator to route a mux using the AMUXBUS. I've got one of the AMUXBUS's completely free of anything else, and all pin have access to the bus. I've also tried manually routing the mux, but it doesn't allow the use of the bus for some reason... I have no idea why.
I have a tested work around that I don't particulary like, which involves wiring all the pins together on the schematic so all the mux inputs and output are short circuited at start (seems the only way I can get the system to actually route those paths?) Then in software I can connect and disconnect all the switches on the AMUXBUS and it works fine. The downside to this work around is at start up all the mux points are shorted...
It seems like I must be missing something here?
So has anyone got this to work in a less bodgy way that what I've come up with? Or has anyone been able to connect and disconnect pins to an AMUXBUS without having wired them up in the schematic (In the debugger it allows me to make the connections, but testing with a DMM they're still open circuit)? I tried putting a "reserve" on the pins but that did nothing.