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...

Latest articles

inpout32.dll vs WinIo

From a previous post, I mentioned WinIo as a nice way of accessing the parallel port from win2k. However, it was slow. The authors said, “I should be using MapPhystoLin() anyways”, whenever I asked about...

Recapping a Samsung 204B monitor

In September 2006, I bought a Samsung 204B SyncMaster monitor for $320 plus tax. It was a 4:3 monitor, ideal for specific tasks like my Logic Analyzer Cart. In July 2024, the monitor stopped working and wouldn’t power...

Reverse engineering the LCD interface

So I was having trouble getting the LCD working initially, so I ended up probing a working HDMI to LCD converter board sold by adafruit. You see, this board was driving my LCD just fine, but my FPGA couldn’t do...

left-justified DAC problems continue

Here you see the analog sound waveform coming out of the DAC at the top in yellow. I think I’m getting closer……I switched from the I2S DAC to a left-justified DAC just because the LJ one is a little...

problem with high density disks

I’m running into an issue with HD, high density, floppies.  The output on the scope looks just fine, but I get a consistent bad checksum on all the tracks.  I’ve tried with and without covering the HD hole...

ISSI memory chip mounted

So I can’t believe how freakin’ tiny those pins are coming off the memory chip.  The pads on the surfboard were huge by comparison.  I actually thought there was a manufacturing defect on the memory chip and...