Search found 331 matches

by marcelk
21 Sep 2019, 06:24
Forum: Hardware and software hacking
Topic: vCPU from ROM (or chained SYS functions)
Replies: 1
Views: 46

Re: vCPU from ROM (or chained SYS functions)

I haven't figured it out yet either. A good application for such a capability will be to host the set of functions for SDC/MMC card loading: for it to load GT1 files anywhere in RAM without true restrictions. On the other hand, with 64K or 128K RAM, this may not be much of an issue. In 32K such a lo...
by marcelk
19 Sep 2019, 14:49
Forum: Hardware and software hacking
Topic: New vCPU instructions? (poll)
Replies: 5
Views: 534

Re: New vCPU instructions? (poll)

We can squeeze in at least two new vCPU instructions without breaking compatibility of existing GT1 files. We can do this by diverting INC and ALLOC, after entry, to another page and continue there. This makes them 6 cycles slower in total, but we can reuse the won space as the landing spot for new...
by marcelk
16 Sep 2019, 17:35
Forum: Kit assembly gallery
Topic: Arrived and running
Replies: 5
Views: 130

Re: Arrived and running

You wouldn't mind attaching a build photo, would you? :?
by marcelk
16 Sep 2019, 14:05
Forum: Kit assembly gallery
Topic: Read this if you need assistance building your Gigatron kit
Replies: 0
Views: 46

Read this if you need assistance building your Gigatron kit

By now, hundreds of enthousiasts have successfully built the kit, and we feel that all things that might possibly cause problems are well known. In case you need assistance, it's advised to first go through the tips and tricks on the Troubleshooting web page. We feel the information there is as good...
by marcelk
16 Sep 2019, 13:47
Forum: Kit assembly gallery
Topic: Blinkenlights steady on
Replies: 1
Views: 32

Re: Blinkenlights steady on

It's advised to go through the tips and tricks on the Troubleshooting webpage. By now with so many kits out there, we feel it's pretty much complete. Then, if still in need of assistance, best contact us on the support mail address listed in the assembly manual. BTW: We haven't seen an non-functioni...
by marcelk
16 Sep 2019, 06:19
Forum: Hardware and software hacking
Topic: Playing with sound
Replies: 5
Views: 155

Re: Playing with sound

Going beyond the original capabilities, I like it. It might be right that the phase shifting only works with triangle. Using wavA should also have the effect of limiting the pulse's amplitude. Have you tried that? After all: it adds a constant to the channel's 6-bit internal value and clips it at 63...
by marcelk
13 Sep 2019, 18:15
Forum: Escape Meta Alt Control Shift
Topic: A tale of 3 programmers
Replies: 0
Views: 62

A tale of 3 programmers

[On-topic for this board because it happened in Cambridge on my way to the Retro Computing Festival at the excellent Centre for Computing History] There I learnt that the Uber app was written by 3 programmers at the very minimum. How do I know? When the credit card you gave it years ago has expired,...
by marcelk
12 Sep 2019, 18:36
Forum: Hardware and software hacking
Topic: Expansion bus
Replies: 69
Views: 5651

Re: Expansion bus

I guess I would have been too lazy and just outputted the size in hex. ;-) Indeed, but once you set your mind to it... The hardest part was to squeeze that conversion into the 96 bytes of a typical code segment. But it exists now, and it sure will come in handy later again. And... I learnt a new al...
by marcelk
12 Sep 2019, 18:26
Forum: Hardware and software hacking
Topic: On serialRaw and buttonState
Replies: 4
Views: 274

Re: On serialRaw and buttonState

the author of the app should know best which video mode works and which doesn't My thinking is that if we trust the owner to assemble the system from 100+ parts, we can surely trust him to select the video mode that works best for him :lol:. Video mode turns out to be a deeply personal thing, we di...
by marcelk
12 Sep 2019, 10:40
Forum: Hardware and software hacking
Topic: Expansion bus
Replies: 69
Views: 5651

Re: Expansion bus

Now with formatting of the entries, and reading more sectors from the same cluster. Tested for exactly 1 card, and block loading is still done byte by byte. Improvements are needed in both areas. Video: https://youtu.be/N4Suhzn2foM I suspect the slower part while listing the entries is actually the ...