Z80 Project Mark 2: More UART Shenanigans
Last updated: 18 Jan 2010 - 22:38
A couple of minor updates you might be interested in. I got a quick demo echoing characters back to the PC working last week. This uses the interrupt on receive feature of the UART setup to trigger a send routine as soon as a character is received. The demo code is available on the Z80 Project page.
It's all fairly simple but there are a few delay loops and things involved. It's also worth checking out the updated Memory and IO schematic as I've updated it with the software reset control for the UART. The only problem I had with this new bit of code was that the compiler wasn't doing exactly what I expected. After a bit of fiddling and dis-assembly I discovered that (probably fairly logically) the org statement doesn't pad the output with anything when generating the binary file, it just offsets the current count for calculating jumps. This of course meant that when I downloaded the binary file I'd generated the first instruction was a jump that missed the entire block of cod
MPASM - memtool firmware
Last updated: 06 Aug 2007 - 22:04
I wrote an article a while ago about making a tool for reading and writing parallel memory chips using a PIC and a USBMOD2 unit. I have finally got around to writing the code out in MPASM (the original was for the PICAXE BASIC programmed PIC.) The code is fairly simple but shows how a PIC can effectively be used in place of complex glue logic.
Contents
- Source memtool.asm file
- Compiled HEX file, memtool.hex
- GPLv3 License