Search found 95 matches

by Sugarplum
30 May 2024, 16:38
Forum: Hardware and software hacking
Topic: What does 'Xpp' mean?
Replies: 2
Views: 6493

Re: What does 'Xpp' mean?

Ah yes, Xpp is also X++. The pp part is "plus plus," so post-increment X.
by Sugarplum
03 Apr 2024, 21:55
Forum: Support
Topic: Controller/Serial input problem
Replies: 5
Views: 8246

Re: Controller/Serial input problem

Yes, that was what I assumed as I was first reading. The controllers operate at different voltage levels and have some quality control issues. As for where the inputs were coming from, I would guess it could be an improperly soldered connection in the controller. It is a serial device, so it would n...
by Sugarplum
06 Nov 2023, 04:53
Forum: Escape Meta Alt Control Shift
Topic: Forum performance issues
Replies: 5
Views: 8437

Re: Forum performance issues

I've noticed that.
by Sugarplum
05 Nov 2023, 20:43
Forum: Escape Meta Alt Control Shift
Topic: 16-bit Gigatron similar machine
Replies: 2
Views: 5895

Re: 16-bit Gigatron similar machine

Thank you Monosonite! I agree, the Gigatron fits the design philosophy well. I'm seriously considering spinning something similar. I think I'd want to play with some working pulls of the limited 16-bit ALUs that were around. They could replace at least 10 chips (and possibly more such as the accumul...
by Sugarplum
01 Nov 2023, 19:40
Forum: Hardware and software hacking
Topic: Bit Serial Revisited.
Replies: 1
Views: 2387

Re: Bit Serial Revisited.

For a Gigatron-similar machine, it might take more than 20 chips to double the ALU width at a reasonable speed. That would likely double the worst-case latency since carry ripples don't scale well. You'd have 2 additional ripples. There used to be a carry generator chip to speed up adders and ALUs, ...
by Sugarplum
22 Oct 2023, 19:27
Forum: Hardware and software hacking
Topic: vCPU Questions and Necessary Details
Replies: 5
Views: 4576

Re: vCPU Questions and Necessary Details

I will ask again: Does any software rely on the row and column data? I don't mean the indirection table, but the current line that is being processed on the screen. I mean, how does it know which line to start on and which indirection entry to look up? How does the clock program know how many second...
by Sugarplum
03 Oct 2023, 11:05
Forum: Escape Meta Alt Control Shift
Topic: 16-bit Gigatron similar machine
Replies: 2
Views: 5895

16-bit Gigatron similar machine

I'm trying to figure out the best way to do a Gigatron-similar machine with a 16-bit native machine under the hood. The vCPU code can still be 16-bit. The memory map could be different. It could use a 16-bit memory map. I know of no old CPU that did that. So how far should I take it being 16-bit? Fo...
by Sugarplum
03 Oct 2023, 04:59
Forum: Escape Meta Alt Control Shift
Topic: Gigatron-related art, media & culture
Replies: 0
Views: 10539

Gigatron-related art, media & culture

Here is a thread for art and media involving the Gigatron.

For instance, I could write parodies about the Gigatron TTL computer.

To the left, to the left,
The ALU is the chips to the left.
The top right the program counter
Near the center the SRAM.

(Apologies to Beyonce)
by Sugarplum
31 Aug 2023, 12:14
Forum: Hardware and software hacking
Topic: SMD Version?
Replies: 9
Views: 4960

Re: SMD Version?

If you want to eliminate the diodes, options include high-speed transistors if you can find them, or PAL/GAL chips. But if you want just a little faster, use Toshiba SMD diodes. You can get them individually and in multi-diode packages. One alternative could be to use an ALU chip. I don't mean the '...
by Sugarplum
31 Aug 2023, 10:24
Forum: Hardware and software hacking
Topic: Design Choices of the Gigatron (and similar designs)
Replies: 0
Views: 7790

Design Choices of the Gigatron (and similar designs)

I looked at the schematics and have some questions. * Could the upper multiplexers driving the memory be replaced by a buffer? I notice that the multiplexers are not wired as I'd expect. The 2nd set of inputs are all tied high. I'd think they'd be tied low to mute the Y register and allow Page 0 ins...