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26 votes
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Was Locomotive BASIC significantly better than Sinclair BASIC?

The big improvement to the language in Locomotive BASIC, compared to Sinclair BASIC (and many other BASICs), was the addition of timer support: AFTER 50,0 GOSUB 320 would call the subroutine at line ...
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24 votes

Was Locomotive BASIC significantly better than Sinclair BASIC?

Was Locomotive BASIC significantly better than Sinclair BASIC? TL;DR: Oh, yes, it was! I'm aware that both Basics were more advanced than the C64 Microsoft implementation, Comparison of C64 BASIC ...
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20 votes
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Is it possible to use an Amstrad CPC464 with a modern monitor or TV

Yes, it is possible. There are a number of ways: If your TV has a SCART connector, you need a cable adapter from DIN 6 to SCART, wired like this (the audio is taken from the audio out using a ...
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16 votes
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Why did the Amstrad CPC use a nonlinear screen memory layout?

Amstrad used an off-the-shelf component, and did the best they could. For generating video addresses, sync timing, etc, Amstrad used the 6845 CRTC, which was originally designed for text displays. In ...
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13 votes

Was the Amstrad's file protection considered secure in 1985?

Secure? No, but much more so than protected BASIC programmes on tape, which merely had a single field set in the tape header that triggered the run once then NEW behaviour. It would definitely have ...
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12 votes
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Why was the Amstrad CPC slow at scrolling

The fundamental issue with scrolling is that, unless your hardware does it for you, it involves moving around the contents of your whole video memory. In other words, scrolling is the type of video ...
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  • 3,762
12 votes

How did Mode 3 on the Amstrad CPC work?

As you can see from the schematic, the Armstrad uses a 6845 compatible display controller together with a custom-made Gate Array or ASIC for video output. The Gate Array also controls the screen modes ...
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12 votes

Was Locomotive BASIC significantly better than Sinclair BASIC?

Considering how much of a rush job Locomotive BASIC was, it's remarkably good. But it's not perfect. Sinclair BASIC has one powerful keyword that Locomotive BASIC lacks: VAL. Sure, Locomotive BASIC ...
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11 votes
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Common practices of programming the AY-3-8910 on Amstrad CPC: via Firmware routines or directly?

Especially for writing the sound registers, it is advisable to use the built-in routines. According to the Schneider CPC firmware guide, the reason is the following: The CPC keyboard is directly ...
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11 votes
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Writting DSK images onto a 3″ floppy for Amstrad/Sinclair computers

I used the dsk2cdt2disc tool to convert a .dsk image to a .cdt tape file. I can then play this tape file via an app (or convert it to audio data) and use a standard Amstrad tape cable to play the ...
10 votes

Writting DSK images onto a 3″ floppy for Amstrad/Sinclair computers

I've written various programs that may help, if the DSK files don't make use of copy protection. If you can get files onto the +3 via the ZXMMC, you can use DU54 at http://www.seasip.info/Cpm/...
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9 votes

Why was the Amstrad CPC slow at scrolling

The two machines had very different video memory layouts. The Spectrum had only 6144 bytes of video bitmap, plus 768 bytes of colour attributes for it. The bitmap was monochrome, but one could set ...
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  • 7,656
9 votes

What are quick ways to load downloaded tape images onto an unmodified 8-bit computer?

This is a wiki answer, so please amend with additional solutions, or improve the ones below: CPC Tape Software Tape images are normally downloaded as a .cdt file, the same file format as the Spectrum ....
9 votes

How long are interrupt requests remembered on the Amstrad CPC?

but I can't find any explicit documentation. The documentation for the Z80 behaviour is in its manual. For the way the CPC hardware handles it, you may need to see these circuits. It may, for example ...
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9 votes
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How long are interrupt requests remembered on the Amstrad CPC?

According to this CPCTech entry: In the CPC the Gate Array generates maskable interrupts, to do this it uses the HSYNC and VSYNC signals from the CRTC, a 6-bit internal counter and monitors the ...
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7 votes

Why was the Amstrad CPC slow at scrolling

The Amstrad CPC was not slow at scrolling. Hardware scrolling as originally intended Ever since the Amstrad CPC was released, even BASIC programs could use vertical hardware scrolling of the whole ...
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7 votes

How did Mode 3 on the Amstrad CPC work?

As stated, mode 3 is an unofficial mode and thus a side effect of hardware implementation, so the circuit is designed to handle only three modes (bit values 00, 01 and 10). This means that bit ...
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7 votes
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A game where you program a robot to fulfill missions

It sounds like you are probably referring to the 1984 release of Chipwits. It was originally released for the Macintosh, and was ported to the Apple ][ and Commodore 64. The screenshot below is from ...
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7 votes

Was the Amstrad's file protection considered secure in 1985?

I'm not familiar with that system, but if users had the ability to protect their own files, then no it was not secure. If you can protect your own files (with known contents) then you have easy ...
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6 votes

A game where you program a robot to fulfill missions

Was it Robot Odyssey? This fulfills most of the criteria in your question except that Robot Odyssey was not isometric - or at least I have never seen an isometric version. It required you to program a ...
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6 votes

Was the Amstrad's file protection considered secure in 1985?

No, it wasn't considered really secure. In fact several programs existed at the time, including small "type-ins" available in magazines for removing that exact protection. There are some of them ...
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6 votes

What method does the game Tau Ceti use to spell-check its commands?

There's another version I found online, but it's the DOS version. In that version, it only used the first three letters. Typing JOYOUS CELEBRATION would be understood as JOYSTICK. The DOS version, ...
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6 votes
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Amstrad CPC6128 disc starting to fail?

'Disc missing' may indicate that the disk is not spinning fast enough, or the index hole sensor is not working properly. The most likely cause is a bad belt. If the computer is left idle for long ...
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6 votes
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Trying to create a filesystem ROM for Amstrad CPC but tape is still waiting

As I was expecting, it was an error in my code :) pelrun was very kind and found the bug (see my question on CPCWiki's forum) so props to him. I'll try to explain the issue: Notice I'm hooking into ...
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6 votes
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Amstrad CPC 6128 - Bench Power Supply Connection Setup

CPC Machines were powered by 5v DC from monitor to the 2.1mm socket on the machine. Any power supply that meets these requirements with the correct polarity should work. The plug has one outer and one ...
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5 votes
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CPC BASIC "CALL" command

Call accepts only integers and pointers as parameters; both are 16 bit values. The parameters are put on the BASIC stack. IX points to the top of that stack. The number of parameters is put into A. ...
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5 votes

What are quick ways to load downloaded tape images onto an unmodified 8-bit computer?

For the ZX Spectrum: Sorted by amount of non standard modern equipment needed (less to more): A smartphone with SpeccyTape (IOS, unfortunately, now unmaintained and not available for 64 bit devices) ...
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5 votes

How long are interrupt requests remembered on the Amstrad CPC?

As far as I know, no /INT is remembered as it is purely level-triggered, as @Raffzahn noted. So losing interrupts in your conditions is just expected. Same design is in ZX Spectrum, with probably a ...
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4 votes

In the Amstrad CPC's Mode 0, what was the design rationale for interleaving the pixel bits?

According to the CPC schematic, the Armstrad uses a gate array to generate video, so we'd need to know how this gate array is programmed for an exact explanation. But expanding on the comment of ...
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4 votes
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Memory sharing mechanism in the Amstrad CPC computer

My best mental reverse engineering of the constraints applied to the CPC bus, based on reading alone, is that it has a period of four cycles. Disclaimer: I'm not much of an electronics person, just an ...
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