Search found 31 matches

by DavidHK
03 Apr 2020, 20:27
Forum: Kit assembly gallery
Topic: Another Gigatron is alive!
Replies: 3
Views: 1522

Re: Another Gigatron is alive!

It sounds very similar to the problems I have with my PS/2 keyboard, quite often it is not working at all and I have to restart everything. I suspect it really is the power supply, at least I get the impression that my chances are different depending on my supply. I guess that some keyboards just dr...
by DavidHK
25 Jan 2020, 17:52
Forum: Escape Meta Alt Control Shift
Topic: UN-unboxing of your Gigatron kit
Replies: 1
Views: 2473

Re: UN-unboxing of your Gigatron kit

Nice to see what goes on behind the scenes. :-) Thanks for doing all this work!
by DavidHK
13 Nov 2019, 19:59
Forum: Hardware and software hacking
Topic: vCPU from ROM (or chained SYS functions)
Replies: 3
Views: 1013

Re: vCPU from ROM (or chained SYS functions)

SYS_Reset_88 (an internal SYS function) then does some reset work, stuffs SYS_Exec_88 into sysFn and provides an argument, reverts vPC and returns to have the same SYS instruction executed again: Ah, yes, that is basically what I was thinking of. (And with branches where each path gets a different ...
by DavidHK
29 Sep 2019, 16:43
Forum: Hardware and software hacking
Topic: Expansion bus
Replies: 96
Views: 38794

Re: Expansion bus

I have now pushed a further change to my emulation work branch that adds a virtual MBR in case the image file starts directly with a FAT32 header. A pure single-partition FAT32 image without an MBR can usually be created easier (by more tools). The next few weeks I probably won't be able to do much ...
by DavidHK
26 Sep 2019, 19:06
Forum: Hardware and software hacking
Topic: Expansion bus
Replies: 96
Views: 38794

Re: Expansion bus

I have now pushed my work so far to my branch (I haven't made a pull request yet, I don't think it is finished at this state). https://github.com/dhkolf/gigatron-rom/tree/dk-libgtemu/Contrib/dhkolf/libgtemu One thing I am not quite happy about is the SD card image. You need not just a partition imag...
by DavidHK
26 Sep 2019, 16:43
Forum: Hardware and software hacking
Topic: Expansion bus
Replies: 96
Views: 38794

Re: Expansion bus

Don't worry, I don't expect CardTest to be more than what the name says -- a test. ;-) But I try to join the test by keeping my emulation somewhere close to the current proposals. And I am also aware that the emulation will not be able to substitute testing with a real SD card -- at least where the ...
by DavidHK
25 Sep 2019, 21:19
Forum: Hardware and software hacking
Topic: Expansion bus
Replies: 96
Views: 38794

Re: Expansion bus

Attached is a screenshot with my work-in-progress so far. Now I have to find out what the issue is, maybe I didn't build the image of the "SD card" properly. At the moment my implementation is far from complete, I am just giving the minimal answers that CardTest.gcl seems to expect -- I don't even c...
by DavidHK
24 Sep 2019, 19:20
Forum: Hardware and software hacking
Topic: Expansion bus
Replies: 96
Views: 38794

Re: Expansion bus

I am currently trying to add the expander to my emulation and I am a bit confused about the MISO lines, maybe I am mixing up the logic levels. As far as I understood from the schematics, the four MISO lines would be pulled high by default, I assumed that to be a 1. To send data from the first SPI po...
by DavidHK
20 Sep 2019, 16:40
Forum: Hardware and software hacking
Topic: vCPU from ROM (or chained SYS functions)
Replies: 3
Views: 1013

vCPU from ROM (or chained SYS functions)

I stumbled over this issue on Github for running vCPU programs directly from ROM: https://github.com/kervinck/gigatron-rom/issues/83 I was pondering about it a while now and I've had questions as to how to handle the program counter and such. One solution might be to add another interpreter, but I w...
by DavidHK
18 Sep 2019, 16:39
Forum: Hardware and software hacking
Topic: summer time
Replies: 2
Views: 1248

Re: summer time

I know I am digging up a really old thread, but I still wanted to give my praise to this demo! The graphics look great and I see this as a promise as to which kind of games the Gigatron is capable of. I hope to see more of this in the future. ;-)