Questions tagged [cpc]
For questions related to the Amstrad CPC series of 8-bit home computers.
26
questions
3
votes
3
answers
423
views
How to run certain .COM files on Amstrad CPC6128?
I have obtained Amstrad CPC6128 with Locomotive BASIC 1.1. Everything works fine except one thing.
I don't know how to properly run certain .COM files. I have tried general commands such as RUN or ...
- 51
7
votes
3
answers
1k
views
How long are interrupt requests remembered on the Amstrad CPC?
I'm trying to emulate an Amstrad CPC 464. Currently, I'm working on interrupt handling and I'm wondering: Some Z80 instructions, like EI or decoding multiple consecutive 0xdd prefixes don't accept ...
- 507
3
votes
3
answers
1k
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What are quick ways to load downloaded tape images onto an unmodified 8-bit computer?
There are repositories of tape software available online, for example CPC Power for Amstrad CPC machines.
What is the fastest and simplest way to load such games onto an unmodified computer, with the ...
- 3,247
3
votes
2
answers
239
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How can I format a higher capacity 3 inch disc on a regular CPC6128?
A standard Amstrad 3 inch disc can be formatted to CP/M Data format on the machine:
single sided, single track, 40 tracks, 9 sectors/track, 512-byte sectors, no reserved tracks, 1k blocks, 2 directory ...
- 3,247
1
vote
1
answer
204
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Amstrad CPC 6128 - Key cap spring missing
Of course the unthinkable happened and I lost one cap key spring while cleaning the keyboard. I am still searching but assuming all things went south, what would be the best solution to replace them? ...
- 127
4
votes
1
answer
380
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Amstrad CPC 6128 - Bench Power Supply Connection Setup
I am definitely at the very beginning of my refurb-journey and learning every step now on the way ... I struggle with the following: I saw a video by Noel's Retrolab where he troubleshooted a CPC.
He ...
- 127
2
votes
3
answers
883
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First time using an Amstrad CPC 6128 Disc Drive [duplicate]
I recently got my first Amstrad CPC and started refurbishing it. Now I wonder, I saw a video, on someone using the RPM test tool for the Amstrad. I found the download online, but this question might ...
- 127
5
votes
2
answers
564
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CPC BASIC "CALL" command
Recently I've been playing around with an Amstrad CPC emulator. I haven't written BASIC code for years, but back in the day I did actually use a CPC for real.
Anyway, looking at documentation online, ...
- 3,045
9
votes
1
answer
391
views
Trying to create a filesystem ROM for Amstrad CPC but tape is still waiting
Some background: I want to create a CPC MicroSD interface, so my first step is trying to hook the CAS* jumpblock entries just like AMSDOS and other DOSes do.
My first goal is to override CAS CATALOG ...
- 251
11
votes
2
answers
356
views
Which addresses does the Motorola 6845 CRTC output during retrace?
I'm trying to understand how the video hardware (CRTC and Gate Array) in Amstrad CPCs works. Specifically, I have a question about the behavior of the refresh memory addresses and row adresses output ...
- 507
3
votes
5
answers
627
views
How to determine where in RAM the current Basic program resides on Amstrad microcomputers?
How can I find where in memory to locate the current Basic program in an Amstrad CPC/PCW family Zilog Z80-based microcomputer?
Is it always the same address?
A different well-known address depending ...
- 6,333
1
vote
1
answer
454
views
Can I connect a Sega Megadrive or Genesis to an Amstrad Cpc monitor?
I'd like to buy an old Sega Megadrive, aka Genesis outside the UK. However I don't have a TV or computer monitor to view the graphics on.
I do however have an Amstrad Ctm644, which is a 15Khz CRT ...
- 3,247
9
votes
2
answers
2k
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In the Amstrad CPC's Mode 0, what was the design rationale for interleaving the pixel bits?
The following tables are modified and corrected from Painting pixels: Introduction to video memory.
Mode 2 - 640x200 (half width pixels), 2 colours
memory bit
7
6
5
4
3
2
1
0
pixel
0
1
2
3
4
5
6
7
...
- 2,527
12
votes
1
answer
1k
views
Why did the Amstrad CPC use a nonlinear screen memory layout?
The screen memory layout on the Commodore 64 in bitmap mode was nonlinear - which incurred a penalty in development time, code size and speed for games using it - because when designing the VIC-II, ...
- 58.4k
3
votes
1
answer
512
views
Amstrad CPC6128 disc starting to fail?
I have an Amstrad CPC6128. I replaced and serviced the drive belt a few years ago, but now I am getting some disc errors. The drive is making noise but a few discs are reporting 'disc missing'. ...
- 3,247
23
votes
3
answers
4k
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Was Locomotive BASIC significantly better than Sinclair BASIC?
The Amstrad CPC range of Z80 machines shipped with
a ROM BASIC, designed and implemented by Locomotive Software. The most well known competitor was the Sinclair ZX Spectrum, also a Z80 machine, with ...
- 3,247
6
votes
1
answer
789
views
Common practices of programming the AY-3-8910 on Amstrad CPC: via Firmware routines or directly?
I'm starting to learn how to program in assembly (z80) on the Amstrad CPC
computer. As an high level developper i find it pretty fun and i learn a lot of
things about computer and CPU architecture.
...
- 163
17
votes
4
answers
4k
views
Why was the Amstrad CPC slow at scrolling
As I understand, neither the Amstrad CPC or the Sinclair Spectrum had any support for hardware scrolling, and arcade conversions struggled compared to the C64 or NES.
However, isometric 3D games such ...
- 3,247
10
votes
5
answers
2k
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A game where you program a robot to fulfill missions
I'm looking for a game. Unfortunately there're only few things I remember:
You had a robot. There was no way to steer it manually, so to solve a room, every step to do had to be programmed in advance
...
- 779
10
votes
4
answers
1k
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Was the Amstrad's file protection considered secure in 1985?
I just reverse engineered the file protection on the Amstrad CPC, which uses two sequences of rotating bytes taken straight out of the AMSDOS ROM to XOR each byte of the file.
If you have SEQa of 13 ...
- 2,527
13
votes
4
answers
4k
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Writting DSK images onto a 3″ floppy for Amstrad/Sinclair computers
For a project I'm working on, I need to write some disks to test on my Amstrad CPC 6128.
I've got some 3″ blank disks, and all my Amstrad computers (CPC and PCW) have 3″ disks, as well as my Spectrum +...
- 18.6k
9
votes
2
answers
264
views
What method does the game Tau Ceti use to spell-check its commands?
This was originally going to be an identify-this-game question but I found the game I was looking for!
I played Tau Ceti when I was a kid and I remember being amazed by how it would accept spelling ...
- 2,527
13
votes
2
answers
2k
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How did Mode 3 on the Amstrad CPC work?
The Amstrad CPC had three official screen modes:
Mode 0: 160x200, 16 colours, 4 bits per colour, 2 wide pixels per byte, bit-interleaved
Mode 1: 320x200, 4 colours, 2 bits per colour, 4 square pixels ...
- 2,527
5
votes
1
answer
692
views
What's the name of this game on the Amstrad that had red-blue separated 3D?
I remember playing a game on the Amstrad 6128 in the '80s or early '90s. It was a space adventure with at least part of the action flying through space and shooting alien ships.
There was an option ...
- 2,527
15
votes
1
answer
1k
views
Memory sharing mechanism in the Amstrad CPC computer
In the Amstrad CPC464 (and I guess it's the same for CPC664 and 6128), the CRTC and the gate array work together to build the display image: every microsecond, the CRTC puts a memory address and a ...
- 18.6k
19
votes
1
answer
6k
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Is it possible to use an Amstrad CPC464 with a modern monitor or TV
During a recent move I lost the monitor for my Amstrad CPC464.
Is it possible to adapt the output of this to work on a modern monitor or on television set?
