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UDB XOR gate: from input pins to blue led (free/libre)

A project log for gelFORTH

a Forth for interactive hardware design on the PSoC 5LP

AndreasAndreas 07/01/2016 at 22:500 Comments

I'm cross-referencing the TRMs with the DSI patent by looking at how the addressing scheme connects the two in a way that makes mathematical sense... and well, I can now compile an XOR gate from gForth to the UDB + routing/DSI system and light up the blue led when I set either of the input pins with my Bus Pirate.

As I had hoped, the PLDs are also reconfigurable during operation, not just the DSI through the Dynamic Configuration RAM.

At first I tried to halt the PSoC before writing the configuration bytes over SWD. But for this to work, I needed to wipe the entire PSoC and write the configuration bytes over SWD without halting.

I used the mostly complete (?) openocd support for the KitProg and PSoC 5LP (by @cyrozap and Andreas Färber) to read and write the configuration bytes from extensible Forth over the tcl rpc interface.

XOR gate: input pins 1'6 & 1'7 to output led 2'1

I've been doing a deep brainstorm on how best to factor the UDB, Routing, and DSI code such that it will work well for partial dynamic live reconfiguration, or in a way, compiling Forth words to Boolean algebra (the CPLD) from the interpreter. Once I've figured more of that out, cleaned-up my experiments, and reached some stability in my approach I think I can release the code to the world. Yay! Thanks for reading!

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