PCW8256 & PCW8512

PCW8256

The PCW8256 and PCW8512 was a range of office computers released in the mid 80’s by the British company Amstrad PLC. In Europe they were sold by the German company Schneider in the early years of production and later sold directly by Amstrad. The machines were based on the Z80 processor running on 4MHz. The computer is built in the Monitor including the 3’ disk drives. This design saved a lot of wiring and space on the desk making it popular with offices and its price tag was 1/3 cheaper than the IBM PC compatible in the UK. As an operating system it uses CP/M Plus and Locoscript ran as a standalone application. The printer is a dot-matrix one and was also included in the price. Later models were sold without the option of the printer as third party companies started to produce their printers compatible with the PCW series.

The software included with the package was very attractive, which was CP/M plus Locoscript, Mallard BASIC, and LOGO Programming Language at no cost. A wide range of games was available as users started to produce free applications and games. The difference between the 512 and 640 model is just memory and disk drives the rest is identical including the motherboard which the 512 model has less ram on board.

PCW8256
UK: £399 (1985) USA: just under $1,000 (1985)
6041K61-58
1985 & 1987
Zilog Z80A CPU running at a frequency of 3.4Mhz
256Kb Ram of which 128K used as a Ram Disk and in basic only 32K Available. No ROM chip as a Bootstrap of 256 bytes is located into a custom chip.
The case enclosure is white and incorporates the 3′ disk drives, the motherboard and the monitor screen. On the left hand side there is a port to connect the keyboard and on the back of the case the expansion port and printer port. The printer is a non-standard type dot matrix printer. The Disk drive is a 3′ non-standard drive manufactured by Matsushita. The Keyboard is a full QUERTY style with additional function keys for programming and shortcuts.
The Display is handled by a custom chip and it can handle resolutions of 90 x 32 in text mode and 720 x 256 (720 x 200 US version) Graphics mode monochrome.
Sound can be produced with an internal beeper.
1 x Keyboard Connector
1 x Expansion Port
1 x Printer Port
1 x DC out Power Supply (for printer)
Internal power supply for Monitor, drives, motherboard and printer.
Dimensions 400mm x 335mm x 310mm (W x L x H) Weight Approx 9.6Kg
More then 800,000 sold across Europe and USA

The Club currently owns 2 of these machines one is the 256 and the other the 512 series. They are cosmetically clean and free from scratches. All manuals, cables, software and printers are in very good state and both machines work perfectly.

Expansion Port

50 Pin Edge Connector
Pin Name Dir Desc
U1 NC N/A No Conn
U2 NC N/A No Conn
U3 GND N/A Ground
U4 GND N/A Ground
U5 +5V OUT +5V DC
U6 +5V OUT +5V DC
U7 NC N/A No Conn
U8 +12V OUT +12V DC
U9 A14 OUT Address
Bit 14
U10 A15 OUT Address
Bit 15
U11 A12 OUT Address
Bit 12
U12 A13 OUT Address
Bit 13
U13 A10 OUT Address
Bit 10
U14 A11 OUT Address
Bit 11
U15 A8 OUT Address
Bit 8
U16 A9 OUT Address
Bit 9
U17 A6 OUT Address
Bit 6
U18 A7 OUT Address
Bit 7
U19 A4 OUT Address
Bit 4
U20 A5 OUT Address
Bit 5
U21 A2 OUT Address
Bit 2
U22 A3 OUT Address
Bit 3
U23 A0 OUT Address
Bit 0
U24 A1 OUT Address
Bit 1
U25 D6 IN/

OUT

 Data Bit 6
L1 D7 IN/

OUT

 Data Bit 7
L2 D4 IN/

OUT

 Data Bit 4
L3 D5 IN/

OUT

 Data Bit 5
L4 D2 IN/

OUT

 Data Bit 2
L5 D3 IN/

OUT

 Data Bit 3
L6 D0 IN/

OUT

 Data Bit 0
L7 D1 IN/

OUT

 Data Bit 1
L8 /RESET OUT Reset
from
CPU
L9 /M1 OUT Machine
Cycle 1
L10 /BUSRQ IN Bus
Request
L11 /INT IN Interrupt
L12 /BUSAK OUT Bus
Acknowledge
L13 /WAIT OUT Wait
State
L14 /WR OUT Write
State
L15 /MREQ OUT Memory
Request
L16 /RD OUT Read
State
L17 /IOREQ IN I/O
Request
L18 NC N/A No
Connection
L19 NSYNC OUT Sync
for
Monitor
L20 VIDEO OUT Video
OUT
1V Pk
L21 MDIS IN Memory
Disable
L22 32MHZ OUT 32Mhz
Clock
L23 Z80CLK OUT Z80
Clock
4Mhz
L24 GND N/A Ground
L25 GND N/A Ground
 

 

Keyboard Connector

4-PIN DIN Chassis Female
Pin Name Dir Desc
1 GND N/A Ground
2 CLK OUT Clock
Sync
3 DATA OUT Data IN
4 +5V OUT +5V DC
 

 

Printer Port

34 Pin Male Connector
(Pin1 Marked with Arrow)
Pin Name Dir Desc
1 VCC OUT +5V DC
2 VCC OUT +5V DC
3 TEST1 IN/
OUT		 Testable
Pin 1
4 TEST0 IN/
OUT		 Testable
Pin 0
5 P27 IN/
OUT		 Data Bit 27
6 P26 IN/
OUT		 Data Bit 26
7 P25 IN/
OUT		 Data Bit 25
8 GND N/A Ground
9 P24 IN/
OUT		 Data Bit 24
10 GND N/A Ground
11 P21 IN/
OUT		 Data Bit 21
12 GND N/A Ground
13 P14 IN/
OUT		 Data Bit 14
14 GND N/A Ground
15 P10 IN/
OUT		 Data
Bit 10
16 GND N/A Ground
17 P17 IN/
OUT		 Data Bit 17
18 GND N/A Ground
19 P13 IN/
OUT		 Data Bit 13
20 GND N/A Ground
21 P11 IN/
OUT		 Data Bit 11
22 GND N/A Ground
23 P16 IN/
OUT		 Data Bit 16
24 GND N/A Ground
25 /P22 IN/
OUT		 Inverted
Data Bit 22
26 GND N/A Ground
27 P23 IN/
OUT		 Data Bit 23
28 GND N/A Ground
29 P12 IN/
OUT		 Data Bit 12
30 GND N/A Ground
31 P20 IN/
OUT		 Data Bit 20
32 GND N/A Ground
33 P15 IN/
OUT		 Data Bit 15
34 GND N/A Ground
 

 

Printer Power DC

DC Power Jack chassis Female
Pin Name Dir Desc
1 GND N/A Ground
2 +24V DC OUT +24V DC
for
printer