Amstrad CPC 464 keyboard

First of the serie, the Amstrad CPC 464 was released in 1984 and discontinued in 1990. It was possible to purchase a CPC 464 with a green screen (GT64) as well as with the standard colour screen (CTM640).

Like most 8bits computers, the CPC has it's OS (aka Firmware) and a BASIC interpreter built-in as ROMs. With a DDI-1 interface, it was also possible to use CP/M 2.2 or 3.0 on a 464.

There is a not very common derivative of the CPC 464, named the CPC 472. This is a CPC 464 with a (non-functional?) 8Kb RAM expansion. Produced in small numbers for the Spanish market to avoid a legal ruling requiring that computers with 64 KB or less RAM must be localized to the Spanish language, including the keyboard and screen messages. The law was subsequently changed to include machines with more than 64 KB RAM so a localised version of the 464 also exists.

Manuals

ROMs

Amstrad Firmware v1.0 (English) (Amstrad 40009)
Amstrad Firmware v1.0 (Danish)
Amstrad Firmware v1.0 (Spanish) (Amstrad 40037)
WANTED: Amstrad Firmware v1.0 (French) (Amstrad 40050)

Locomotive BASIC 1.0 (Amstrad 40009)

Bootscreens

Here are some screenshots of what a CPC 464 shows when switched on (with a color monitor/tv set).

External Links

Further informations about the CPC 464 can be found on these websites:

Specifications

Frequencies

Z80 CPU at 4MHz.
AY3-8912 at 1MHz.
CRTC 6845 at 1MHz.
VGA at 16MHz.
300Hz interrupt.

Video

50Hz (PAL) or 60Hz (NTSC) framerates.
27 colors palette.
3 screen modes (official):
- MODE 0 : 160×200 with 16 colors.
- MODE 1 : 320×200 with 4 colors.
- MODE 2 : 640×200 with 2 colors.
Up to 64Kb Video-RAM.
RGB with composite sync outputs.

Audio

AY3-8912 Soundchip, 3 channels, 7 octaves.
Built-in internal speaker (mono) with volume control.
Stereo jack output.

Memories

64Kb of RAM.
32Kb of ROM:
- 16Kb for the Amstrad Firmware v1.0
- 16Kb for the Locomotive BASIC 1.0

Mass Storage

Built-in Tape Deck (software controlled write speed).

Keyboard

74 keys with numeric pad.

Dimensions & Weight

Width: 580mm
Height: 170mm
Depth: 70mm
Weight: 2.4Kg

Power Supply

Input DC 5V, 2A

Connectors

Audio Jack
Joystick
Printer Port
Expansion Port
Monitor output
DC 5V Input

Unlike other models, all the CPC 464 have PCB edges only connectors (even those produced by Schneider) for the printer and expansion/floppy ports.

Printer port

Pinout

Pin	Description	Pin	Description	Pin	Description	Pin	Description
1	/STROBE	10	BUSY	19	GND	28	GND
2	D0	11	NC	20	GND	29	NC
3	D1	12	NC	21	GND	30	NC
4	D2	13	NC	22	GND	31	NC
5	D3	14	GND	23	GND	32	NC
6	D4	15	NC	24	GND	33	GND
7	D5	16	GND	25	GND	34	NC
8	D6	17	NC	26	GND
9	GND (D7)	18	NC	27	GND

PCB Edge connector

Note

The Amstrad CPC has a 7bit only printer port (D7 is fixed to zero). It's outputs (D0-D6) can be used with any TTL-compatible chips (including the widely-available 74 series logic chips).

On power up or system resets the outputs are cleared.

Expansion port (aka Floppy port)

Pinout

Pin	Description	Pin	Description	Pin	Description	Pin	Description
1	SOUND	16	A2	31	/IORQ	46	CURSOR
2	GND	17	A1	32	/RD	47	L.PEN
3	A15	18	A0	33	/WR	48	/EXP
4	A14	19	D7	34	/HALT	49	GND
5	A13	20	D6	35	/INT	50	CPUCLK (4MHz)
6	A12	21	D5	36	/NMI
7	A11	22	D4	37	/BUSRD
8	A10	23	D3	38	/BUSAK
9	A9	24	D2	39	READY
10	A8	25	D1	40	/BUS RESET
11	A7	26	D0	41	/RESET
12	A6	27	VCC (+5v)	42	/ROMEN
13	A5	28	/MREQ	43	ROMDIS
14	A4	29	/M1	44	/RAMRD
15	A3	30	/RFSH	45	RAMDIS

PCB Edge connector

Joystick

Pinout

Pin	Description
1	Up
2	Down
3	Left
4	Right
5	Fire 3 (undocumented)
6	Fire 2
7	Fire 1
8	Ground
9	Ground 2 (for second joystick)

DB9 Male connector

Note

Joystick are just a bunch of switches that connect a direction or fire pin to the ground.
Atari joysticks are 100% compatible with the CPC.

Monitor output

Pinout

Pin	Description
1	Red
2	Green
3	Blue
4	Sync
5	Ground
6	Lum.

DIN6 Female connector

Audio Jack

Note

This audio output is aimed to go through an amplifier. The signals are not strong enough to directly drive an headphone (you won't hear much sound if you do it).

DC 5V/2A Input

Keyboard layout

The CPC 464 has 4 keyboard layouts. Each one of them is associated to a specific firmware version with the corresponding keymap and charset.

QWERTY

QWERTY (Spanish)

QWERTY (Danish)

Not enough infos about this.
WANTED: Danish CPC 464 keyboard picture

AZERTY (French)

Circuit Diagram

CPC 464

This circuit diagram refers to the original release of the CPC 464 motherboard. Updated schematics of the revised motherboard can be found in the amendment service manual.

Closeup views

Cassette Deck

Pictures

Original release

Original pictures taken by Zik/Futurs'

Revision 1

The keyboard has flat keys and is connected to the motherboard with a ribbon cable.

There's two spaces to put either a 40007 or 40010 Gate Array and both were actually used (you can easily spot those with the 40007 Gate Array because it was mounted with the usual ugly heatsink). The pictures below show the motherboard with a 40010 Gate Array.

WANTED: Better pictures.

Revision 2

The motherboard is half the size of the original CPC464 motherboard. The keyboard has flat keys and is connected to the motherboard with a ribbon cable. Due to the size reduction of the PCB, the joystick and audio-jack connectors moved on the left side of the case.

Amstrad CPC464 keyboard provided by Power/Ukonx. Original pictures taken by Zik/Futurs'

Revision 3 (aka cost-down)

The motherboard is much smaller (about 1/4 the size of the original CPC464 motherboard). The functions of the CRTC 6845 and Gate Array have been combined into a single ASIC custom IC. The keyboard has flat keys and is connected to the motherboard with a ribbon cable.

WANTED: Better pictures.

documentations/hardware/amstrad.cpc464.txt · Last modified: 2009/12/22 12:38 by grim