techtravels.org

inital results on error correction

While I have yet to actually implement the full-scale error correction as I want to, I did some manual tests today. I basically took a track that I was erroring out on, and swapped in 1-bit away values for the bad bytes.  In some cases, it appeared...

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a little code review today

While my send UART code has been pretty solid for some time, I’ve always though my receive uart code needed doublechecked and worked on. I spent some time today just going through the code, graphing out some...

writing merged USB comm code

Now that I have USB receive working in the main PC code, its time to merge the USB transmit(and receive for commands) into the main SX code. I have two pseudo-code versions written. 1> First version uses the ISR to...

new design

I took David’s advice, and I rewrote the code last night. Some highlights: 1. ISR is entirely in assembly. Although I haven’t manually counted, it appears to be about 400ns in length. 2. ISR triggers only...

PC xfer working now, timing in order

Welp I pretty much solved the big problems I encountered over the past couple weeks. Ground issues — turned out I was attaching ground of one interface to Vdd on another interface. That was solved by actually...

new design on SX software

Welp, I’m having trouble tweaking my existing SX code. If I modify the timing of the current code, I’m getting all garbage output — even adjusting small amounts to one side or the other, produces much...

today’s successes

I really stumbled on some stuff, and I think I have traction on a couple of problems. 1. My sizes are absolutely perfect. For me, this is a big milestone. This tells me alot. I’m getting perfect distances between...

Good news. Floppy now under SX control

OK, so I finally bit the bullet and have the floppy drive under direct SX control. I have my amiga power supply, which is a modified PC supply with harddrive leads powering the drive directly with +12v and +5v.  I also...

feasability of writing disks

While there are some other bug fixes and documentation to be done on what’s already been implemented, I started thinking about writing ADF’s to disk over the last few days. While the hardware part of it is...

Logicport screenshots and project file

I thought this might be neat to put up. Sorry about the high-res image but you lose too much when it compresses it. Click here for the screenshot. Also, I uploaded the .LPF project file which can be viewed for free with...