Search found 101 matches

by monsonite
21 Nov 2023, 21:41
Forum: Hardware and software hacking
Topic: Emulating other CPUs
Replies: 0
Views: 2738

Emulating other CPUs

Hi All, This a topic that has been simmering on the back-burner, ever since Marcel astounded us all with the v6502 and the Apple and Microchess emulation. As a Z80 enthusiast, it would be great to emulate the Z80, but for it's day, the Z80 is a surprisingly complex cpu, with 158 instruction "ty...
by monsonite
04 Nov 2023, 13:59
Forum: Escape Meta Alt Control Shift
Topic: 16-bit Gigatron similar machine
Replies: 2
Views: 2024

Re: 16-bit Gigatron similar machine

Personally, I feel that the Gigatron achieves all that was ever intended of it, plus a lot more. It should provide the inspirational basis for new architectures, possibly with different end goals, and these priorities may be varied, depending on the application. I would like to see a hardware "...
by monsonite
01 Nov 2023, 16:51
Forum: Hardware and software hacking
Topic: Bit Serial Revisited.
Replies: 1
Views: 1640

Bit Serial Revisited.

Until about 1952 all computers used a bit-serial architecture in order to reduce the complexity of the hardware. This philosophy continued into the 1970s, so that desktop and handheld electronic calculators could be made economically. The RCA1802 uses a bit serial ALU, to keep the transistor count d...
by monsonite
01 Nov 2023, 15:43
Forum: Hardware and software hacking
Topic: 10MHz, 12.5MHz and Beyond!
Replies: 45
Views: 53493

Re: 10MHz, 12.5MHz and Beyond!

Good Work, Hans.
by monsonite
01 Nov 2023, 15:23
Forum: Kit assembly gallery
Topic: Another Gigatron TTL in Finland
Replies: 15
Views: 10163

Re: Another Gigatron TTL in Finland

Good Work! I like the purple PCB. With a bit of work a Gigatron can be pushed to 10MHz clock, or 12.5MHz with swapping some of the ICs for 74F (fast) series). Whilst I personally have little need for low resolution colour graphics and sound,the Gigatron is a remarkably versatile and fast CPU, capabl...
by monsonite
02 May 2022, 20:18
Forum: Hardware and software hacking
Topic: High Noon - Gigatron versus Z80 shoot out.
Replies: 0
Views: 3096

High Noon - Gigatron versus Z80 shoot out.

The greatest advantage that the Gigatron has over any other 8-bit microprocessor is that all of it's native assembler instructions execute in a single clock cycle. I am currently exploring the Gigatron assembly language, and since I have had experience in Z80 machine code, I thought I would configur...
by monsonite
02 May 2022, 19:39
Forum: Hardware and software hacking
Topic: Lies, Damned Lies and Benchmarks.
Replies: 27
Views: 5778

Re: Lies, Damned Lies and Benchmarks.

What would have been the price of Gigatron in the 70s? ICs were not as cheap, especially SRAM. Still a good deal compared to a Cray1... I have found various magazine adverts in online archives for TTL ICs from the 1970s. Almost all of the TTL ICs used in the Gigatron were available by 1975. Typical...
by monsonite
29 Apr 2022, 14:59
Forum: Hardware and software hacking
Topic: ROMv5a - Intel hex file required
Replies: 0
Views: 3158

ROMv5a - Intel hex file required

EDIT - problem solved. :D I found an online utility that took the binary file and spat it out in the correct Intel hex format :100000000000188018C0C17C0001D60100FF690003 :10001000CA00C2006900EC0B00FF6900CA00610061 :10002000F0140101FC05820000FFC200EC16A001E3 :100030000100EC15A0010001188018C00000D218C...
by monsonite
07 Apr 2022, 10:39
Forum: Hardware and software hacking
Topic: Gigatron Assembly Language
Replies: 3
Views: 1808

Re: Gigatron Assembly Language

Thankyou for your excellent explanation.

I could not understand exactly what the AND / OR instructions were doing.

I was trying to work out how the carry was detected from Cout, not realising that it could be determined from the sign bit of the two operands.

This makes it clear now.

Thanks
by monsonite
06 Apr 2022, 16:32
Forum: Hardware and software hacking
Topic: Gigatron Assembly Language
Replies: 3
Views: 1808

Gigatron Assembly Language

It's unlikely that most Gigatron owners get involved with the native 8-bit assembly language - because it is very much wrapped up in the ROM. However, I have been working on a hardware simulation, using H. Neemann's "Digital" simulator, and I am now working at the native assembly level. I ...