Electron, BBC B, B+, Master 128 and Master Compact port pinouts.
Connector: Cassette
Type: 7-pin DIN
(See Graphic 1)
Pinout: 1 Output
2 0V
3 Input
4 Output
5 N/C
6 } Motor Control
7
Connector: RGB
Type: 6-pin DIN
(See Graphic 2)
Pinout: 1 Red
2 Green
3 Blue
4 Sync
5 0V
6 +5V
Connector: UHF
Type: Phono
(See Graphic 3)
Pinout: 1 UHF
2 Ground
Connector: Video Out
Type: Phono
(See Graphic 4)
Pinout: 1 Video
2 Ground
BBC Model B, B+ and Master 128.
Connector: RGB
Type 6-pin DIN
(See Graphic 5)
Pinout: 1 Red
2 Green
3 Blue
4 Sync
5 0V
6 +5V
Connector: RS 423
Type: 5-pin DIN
(See Graphics 6)
Pinout: A) Data in
B) Data Out
C) 0V
D) CTS
E) RTS
Connector: Cassette
Type: 7-pin DIN
(See Graphic 7)
Pinout: 1 Output
2 0V
3 Input
4 Output
5 N/C
6 } Motor Control
7
Connector: Analogue in
Type: 15 way D-type socket
(See Graphic 8)
Pinout: 1 +5V 9 light pen strobe (notLPSTB)
2 0V 10 digital switch input (I1)
3 0V 11 voltage reference (VREF)
4 CH3 12 CH2
5 analogue ground 13 digital switch input (I0)
6 0V 14 voltage reference (VREF)
7 CH1 15 CH0
8 analogue ground
Connector: Econet
Type: 5-pin DIN
(See Graphic 9)
Pinout: 1 Data +
2 0V
3 Clock +
4 Data -
5 Clock -
Connector: UHF
Type: Phono
(See Graphic 10)
Pinout: 1 UHF
2 Ground
Connector: Video Out
Type: BNC
(See Graphic 11)
Pinout: 1 Ground
2 Video
(See Graphic 12)
Connector: Disc Drive
Type: 34-way IDC
(See Graphic 13)
Pinout
1 0V 10 S0 19 0V 28 WR PCT
2 (S/SEL 8") 11 0V 20 29 0V
3 0V 12 S1 21 0V 30 R/DATA
4 (INX 8") 13 0V 22 W/DATA 31 0V
5 0V 14 N/C 23 0V 32 S/SEL 5¼"
6 N/C 15 0V 24 WR/EN 33 0V 7 0V
7 OV 16 MOTOR 25 0V 34 (RDY 8")
8 INX 5¼" 17 0V 26 TK0
9 0V 18 notDIR 27 0V
Connector: Parallel
Type: 26-way IDC
(See Graphic 14)
Pinout:
1 STB 8 0V 15 PA6 22 0V
2 0V 9 PA3 16 0V 23 N/C
3 PA0 10 0V 17 PA7 24 0V
4 0V 11 PA4 18 0V 25 N/C
5 PA1 12 0V 19 ACK 26 N/C
6 0V 13 PA5 20 0V
7 PA2 14 0V 21 N/C
Connector: User Port
Type: 20-way IDC
(See Graphic 15)
Pinout:
1 +5V 6 PB0 11 0V 16 PB5
2 CB1 7 0V 12 PB3 17 0V
3 +5V 8 PB1 13 0V 18 PB6
4 CB2 9 0V 14 PB4 19 0V
5 0V 10 PB2 15 0V 20 PB7
Connector: 1MHz Bus
Type: 34-way IDC
(See Graphic 16)
Pinout:
1 0V 10 PGFC 19 D1 28 A1
2 R/W 11 0V 20 D2 29 A2
3 0V 12 PGFD 21 D3 30 A3
4 1E 13 0V 22 D4 31 A4
5 0V 14 RS 23 D5 32 A5
6 NMI 15 0V 24 D6 33 A6
7 0V 16 audio in / out 25 D7 34 A7
8 IRQ 17 0V 26 0V
9 0V 18 D0 27 A0
Connector: Tube
type: 40-way IDC
(See Graphic 17)
Pinout:
1 0V 11 0V 21 0V 31 +5V
2 R/W 12 D0 22 D5 32 A2
3 0V 13 0V 23 0V 33 +5V
4 2E 14 D1 24 D6 34 A3
5 0V 15 0V 25 0V 35 +5V
6 1RQ 16 D2 26 D7 36 A4
7 0V 17 0V 27 0V 37 +5V
8 TUBE 18 D3 28 A0 38 N/C
9 0V 19 0V 29 0V 39 +5V
10 RS 20 D4 30 A1 40 N/C
Master Compact
The majority of the Master Compact connectors are the same as the Model B and Master, however there are some different and additional connectors which are documented below.