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

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...

Intronix LA1034

I’m seriously looking at the Intronix LA1034 logic analyzer. It’s a USB PC-based logic analyzer.  34 channels, samples up to 500mhz, and has nice trigger options, etc.  I’ve downloaded the software...

working cause of bit errors

I think I’ve stumbled on something. I don’t think I’m capturing enough data. 13,824 has been my magic number forever.  It was larger than the 13,800 that Marco used in afr.c.  But I’m beginning...

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...

Parts ordered for the A501 replacement card

I placed an order yesterday for some prototyping parts to get this project off the ground. Some of the key parts are: ISSI 256kx16 SRAM chips. IC SRAM 4MBIT 25NS 44TSOP A surfboard to do 44-pin TSOP II to DIP.  Wish me...

Armiga Project

Here’s a cool project that I have some involvement with, the Armiga Project. This is basically an ARM-based emulation platform for the Amiga 500 that uses normal Commodore Amiga floppy disks! Pretty cool, and I...

added byte-sync to my transfer routine

Well, after much thought, pondering, and discussion with David, I finally implemented a working byte-sync routine to my SX software. I don’t have it fully working with the PC side software yet, because this...