Questions tagged [homemade]
for questions about homemade or homebrew retrocomputing hardware and software
15
questions
9
votes
3
answers
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What is the purpose of the M1 pin on a Z80
I've been looking through bits of documentation about the (sadly recently discontinued) Z80 processor and the machines people have built with it. One thing I noticed is pin 27, called "M1", ...
- 243
8
votes
1
answer
999
views
What EPROMs should I use to make my own NES cartridges?
I want to make my own NES cartridge, but I don't know what the correct type of ROM chip would be.
I am specifically thinking about the simplest PCB that works, an NES-NROM-128 which consists of a 16 ...
- 1,680
8
votes
1
answer
394
views
Are there any homebrew games (or demos) for the Timex/Sinclair 2068?
I know there has long been a thriving homebrew scene for games and demos for the original Sinclair Spectrum range and also for the Russian and Eastern Bloc Spectrum clones.
But I expected some old ...
- 6,948
16
votes
3
answers
3k
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Z80 is making weird relative jump errors. How can that be?
My little Z80 breadboard project got stuck in the mud where I am pulling my hair out. It looks like the CPU is making a calculation error on a relative jump. Here is my code, and I don't think ZX ...
- 1,387
4
votes
1
answer
1k
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Commodore 64 board dimensions
What are the dimensions of the C64 motherboard? I am specifically asking this because I am considering using a 64C case (these still seem to be in production) for an 8-bit homebrew machine. I wonder ...
7
votes
1
answer
1k
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What is the Nintendo 64 IPL3 and how could it be created by Rust developers?
I was delighted to learn there is an integrated toolchain for Rust development that supports the Nintendo 64. According to the documentation:
For copyright purposes, the IPL3 binary is not included ...
- 61k
10
votes
1
answer
1k
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Can you program an arcade game and have MAME or another emu run it?
I know Mame works with drivers for each game or hardware, and it checks for specific ROMs, and I guess it might check also for some checksum to verify the ROMs integrity.
Is there some way you could ...
- 321
4
votes
5
answers
1k
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How to teach the Z80 to count milliseconds and microseconds like Arduino?
I make a homebrew (for hobby) game console on Z80A, and I need help.
Now I'm stuck - I need to be able to count milliseconds and microseconds in the code. For example, how it is done in Arduino :
...
- 611
12
votes
4
answers
3k
views
Smallest/Simplest, modern pure relay computer with at least 4-bits data words
There are a lot of designs out there of modern home made relay computers (not just ALUs but real computers -let's call them Turing complete, although Turing complete is not enough for having an ...
- 539
3
votes
1
answer
1k
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Can't get the AY-3-8913 sound chip to work with my z80 (added schematic)
I'm trying to get the ay-3-8913 sound chip to work with my z80 but so far I haven't gotten any sound output yet. I know the chip, my amp circuit and the clock circuit work because it works when I ...
- 394
11
votes
3
answers
1k
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z80 crashes after executing some instructions
I'm building my own Z80 computer but I'm having a very strange problem.
Consider this code:
ld a,0xaa
out (00),a
jp a
That works as expected, outputting 0xaa on port 0x00. Now consider this code:
...
- 394
1
vote
1
answer
403
views
How to I give instructions to a Z80 CPU [duplicate]
I found a Z80 CPU lying around my house. I've search all over the Internet but I still don't know how do I input stuff and tell it what to do. Help me please
- 11
24
votes
3
answers
8k
views
Wiring a Zilog Z80
I've recently got hold of an old Zilog Z80 microprocessor and I know how to clock and test it. I do not however know how to connect RAM, I/O ports, control switches (for programming instructions into ...
- 343
7
votes
1
answer
742
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Is there a KiCad library with parts used in retrocomputers?
I ran into this question a few times and couldn't find any acceptable answer:
Once I was trying to reverse engineer a card that had chips like Intel's 8255 PPI, 8226 bus drivers and some other ICs. I ...
- 1,344
8
votes
2
answers
796
views
Homemade ROM cartridge for Thomson TO7/70 home computer
I recently acquired a Thomson TO7/70 home computer. It came without any MEMO7 cartridges (ROM cartridges) that are necessary to properly use it. I found images of the ROMS, and a schematic, so in ...
- 28.4k