Search found 20 matches

by xopr
22 Jan 2020, 16:26
Forum: Hardware and software hacking
Topic: GTOS
Replies: 3
Views: 272

Re: GTOS

I'm trying to catch up on all the awesome new features and dug up a perfboard SD card interface that I haven't touched for 11 years, back when I didn't even knew what Arduino was (I was using MyAvr with Petit FatFs ) So when I tried it on the Gigatron (without any sign of life), I decided to test wi...
by xopr
16 Jan 2020, 14:00
Forum: Hardware and software hacking
Topic: Expansion bus
Replies: 87
Views: 10217

Re: Expansion bus

How does this issue occur? /SS is an output, and should always be driven by the host aka Gigatron .... Is this something we should address on the Gigatron side? I might have to add that it is subject to the Arduino's reset pin on the ICSP header which I guess is not intended for SPI slave operation...
by xopr
15 Jan 2020, 16:28
Forum: Hardware and software hacking
Topic: Expansion bus
Replies: 87
Views: 10217

Re: Expansion bus

Hi, I'd like to build expansion bus, but I'm little confused - where is the latest PCB/BOM files? (seems it's scattered over the messages). Thanks in advance. This topic indeed becomes a bit of a challenge to gather all important snippets from.. Here is a short summary to get on par (leaving SD/MMC...
by xopr
01 Aug 2019, 17:36
Forum: Hardware and software hacking
Topic: Expansion bus
Replies: 87
Views: 10217

Re: Expansion bus

Thanks, Ken :D I've just updated the Terminal code and Arduino code , but I have to add some remarks: the code is still in really bad quality (mediocre at best) the Arduino needs the reset-on-serial disabled or the terminal server won't recognize the serial port correctly; newer revisions have a scr...
by xopr
30 Jul 2019, 21:35
Forum: Hardware and software hacking
Topic: Expansion bus
Replies: 87
Views: 10217

Re: Expansion bus

Not sure if it is the first connected Gigatron, but here is a teaser video where I connect over (Arduino) USB serial to my laptop: https://youtu.be/vtE6ngzq8qA (Sorry for the terrible video quality) The blurry text on the left Linux terminal executes systemctl start serial-getty@ttyACM0.service (aft...
by xopr
27 Jul 2019, 19:25
Forum: Hardware and software hacking
Topic: Expansion bus
Replies: 87
Views: 10217

Re: Expansion bus

Thanks Marcel and Ken. To be fair, I'm just standing on the shoulders of giants here :) Also, I want to mention that the original Newline function is genius to a level of mind boggling (for me least); it took me two days to figure out how the ScreenPos upper byte and videoTable offset were aligning ...
by xopr
24 Jul 2019, 16:42
Forum: Hardware and software hacking
Topic: Expansion bus
Replies: 87
Views: 10217

Re: Expansion bus

It took me a while to get everything on track (and I'm not sure if I can spend more time on it this week), but I have a proof of concept written in C that outputs the Gigatron's keyboard input on screen (using tinyfont) and to the SPI0 port as well. Here is my result: https://youtu.be/R9liFeYZV7E Th...
by xopr
21 Jul 2019, 16:25
Forum: Hardware and software hacking
Topic: Expansion bus
Replies: 87
Views: 10217

Re: Expansion bus

Thanks for the elaborate update, Marcel: this was a good kickstart for me. The soldering and modification was more or less painless; here are some snapshots of my progress (sorry for the bad quality pictures): expander_cutoff.jpeg Note that I had to cut off a bit of Expander J2 pins 4, 9 and 13 (Gig...
by xopr
06 May 2019, 08:56
Forum: Hardware and software hacking
Topic: Expansion bus
Replies: 87
Views: 10217

Re: Expansion bus

... We have a few extra of those SPI prototype boards for those interested in playing along. They need the same wiring patches as I posted in this thread earlier, and assuming you can reprogram your own EPROM and have your own chips, we can share them "as-is" for just the postage costs. Just drop u...
by xopr
03 May 2019, 14:09
Forum: Hardware and software hacking
Topic: Expansion bus
Replies: 87
Views: 10217

Re: Expansion bus

... Cool! It can work with some relocation :-). Under BASIC, you need to find another place in memory to store this program. BASIC itself is sitting at 1280 / 0x500, and it has more variables in the zero page than WozMon. ... I dug around the memory model, how BASIC is using the remaining memory an...