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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Finally had some luck with FPGA board

So I bought an FPGA eval board and a book on Verilog awhile back.  I made some progress learning things, and had some simple things like UARTs, writing to the LCD, and even some small VGA software(hrrrm, maybe I should...

updates with FRAM access

My initial attempts to write to the FRAM used SX/B commands like SHIFTIN and SHIFTOUT. These operated at a slow rate of about 83kbits/s. It did work and functioned as a good test of the hardware setup. Now that...

Good news good news. First perfect .adf

Good news indeed! I’ve managed to create a fully functioning .ADF from a floppy.  I matched the output from my hardware/software combination with a “transdisk” output, and it matches exactly. I used...

great performance increases

Today I’ve worked on optimizing the performance of the AFP reader and have made great strides. My original track times were nearly 475ms. This was 300ms reading the actual disk, 125ms transferring, and process...

data rate vs throughput

Although I’m transmitting from the Parallax SX microcontroller to the PC via USB at a data rate of 2mbps, the actual throughput is much less.  First, there is some overhead, namely start and stop bits, which is...

amiga floppy project activity

I don’t know how interesting this is, but I thought I’d throw it up anyways. I exported the posts and comments tables from the mysql database, imported into Excel, and then created an activity graph of the...

USB uart send and receive

Good news, good news. After banging my head on the same problem for the last three hours, I’ve finally made some more progress. Using option #2 from the previous post, I’ve written two non-isr based software...

Minor problems on techtravels.org email

I recently discovered a problem where email directed to techtravels.org accounts was bouncing. It’s been fixed. If you’ve emailed something over the last couple months and didn’t get a reply, please...

java client works

Well I’m producing correct .ADF’s with the new java client. The terminal mode is also finished and working. I have some various odds and ends to wrap up with it, namely allowing the user to save his...

minor success at 2:00am

well I’ve got MFM flowing from the PC drive now.  A couple of things: Pins 10 and 14, the pins I’ve been using since last night, appear to be correct. Pin 10 is the motor lead.  Dropping a corresponding SX...