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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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14 votes
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How was text handled on the Amstrad CPC 464?

All text is painted as bitmaps. The highest-resolution built-in mode is 640x200 pixels, so that provides an 80x25 text mode. 80-column modes were used in business software (e.g. DBase II) and even in ...
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13 votes
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Why could you hear an Amstrad CPC working?

There seems to be a slight misunderstanding: The CPU in a computer is (almost) never doing nothing (excluding power save states which was largely unknown at times the Amstrad was en vogue). So there's ...
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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

How was text handled on the Amstrad CPC 464?

To elaborate on drawing text on Amstrad CPC and its screen addressing: The first row of every character position on screen is at the memory address range from &c000 to &c7ff, and thus can be ...
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9 votes
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How does the Motorola MC6845 in the Amstrad CPC 464 behave on start-up?

The short answer is that the contents of the CRTC control registers are indeterminate after power-up, and that the CRTC will nevertheless operate according to their contents immediately after /RES is ...
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7 votes

Why could you hear an Amstrad CPC working?

What you possibly can hear, however, is the CPU repeatedly doing the same thing, like operating in tight loops that can, through electrical or mechanical interference (with the monitor or audio signal,...
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7 votes

Why CPC464 display is less stable while reading from cassette?

This effect is typically caused by a conflict of interrupts. My experience of the CPC specifically is limited, but I've seen this on other machines from this era. Most computers of this vintage used ...
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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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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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4 votes

cbm prg studio for the Amstrad

The nearest I can think of — though still very far from CBM prg Studio's integration — is CPCtelera. It's mostly for C development, and the BASIC and debugging components that make prg Studio so ...
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3 votes

How was text handled on the Amstrad CPC 464?

The Amstrad CPC range supported 3 basic screen modes: mode 0 - 160x200, or 20x25 characters, with a palette of 16 colours mode 1 - 320x200, or 40x25 characters, with a palette of 4 colours mode 2 - ...
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1 vote

Amstrad CPC 464 tape deck loads, but makes grinding scratching noise

It's likely that parts of the drive mechanism are worn, out of adjustment, or need lubricating. Tape cassette decks are all very similar to each other in principle, so I suggest looking for a generic ...
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1 vote

Which computers had features added purely for tax reasons?

In Spain the computers must have the ñ key. The old ZX Spectrum 48K didn't have it. The ZX Spectrum + 2 solved it. The law says: "Todos los aparatos de funcionamiento eléctrico o mecánico qué se ...
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