Interactive Connector & Port Pinout Reference

8-Pin DIN (262° Horseshoe) / 5-Pin DIN (180°)

Composite CVBS, separated S-Video Luminance (Y) and Chrominance (C), and Mono Audio output for the C64, C128, SX-64, Plus/4, C16, and VIC-20.

23-Pin D-Sub (DB23 Male on Amiga / DB23 Female on Cable)

15.6 kHz Analog RGB (0.7 Vpp), 4-bit Digital RGBI, Composite/Horizontal/Vertical Sync, Genlock clocks, and +12V/+5V/-5V power rails on every Amiga.

6-Pin DIN (240° Circular — DIN 45322)

Side-by-side 6-pin 240° DIN RGB monitor pinouts and SCART resistor values for both the Amstrad CPC 464/6128 and the BBC Micro / Acorn Electron.

9-Pin D-Sub Female (DE-9F on C128)

Digital 16-colour TTL RGBI (CGA-compatible) plus a built-in 80-column Monochrome Composite Video signal on Pin 7 for the Commodore 128's MOS 8563/8568 VDC.

13-Pin Circular DIN (Male Plug / Female Socket on ST)

Carries both 15.7 kHz Color Analog RGB (Low/Med Res) AND 35.7 kHz / 71.2 Hz High-Res Monochrome (640x400), automatically switched by grounding Pin 4 (/MONO DETECT).

8-Pin DIN (262° Horseshoe on QL & +2A/+3; 270° Circular on 128K & Grey +2)

TTL & Analog RGB, Composite Sync, and Composite PAL video pinout for the Sinclair QL and ZX Spectrum 128K / +2 / +2A / +3.

5-Pin DIN (180° — DIN 41524)

Covers the Oric-1/Atmos 5-pin DIN RGB + CSYNC output (and why passive Oric SCART cables show a black screen without +5V blanking!) plus the Dragon 32/64 5-pin Composite A/V port.

5-Pin DIN (180° — DIN 41524)

Composite Video, Mono Audio, and separated S-Video Luminance (Pin 1) & Chrominance (Pin 5) for the Atari 800, 800XL, 65XE, and 130XE.

5-Pin / 6-Pin DIN (TI-99/4A) & 8-Pin 262° Horseshoe DIN (MSX)

Covers US 5-pin Composite & European 6-pin Component YPbPr on the TI-99/4A, plus the critical Japanese vs. European 8-pin RGB DIN difference on MSX computers.

10-Pin (2×5 0.1" IDC Box Header) & 7-Pin (0.156" Molex Inline Header)

Covers the Tandy CoCo 3's underside 10-pin (2×5) Analog RGB header (J1) for SCART/OSSC and the Commodore PET's internal 7-pin (J7) TTL CRT monitor header.

7-Pin DIN (270° Circular — DIN 45329)

Supplies regulated +5.0 V DC (for logic/DRAM) and isolated 9.0 V AC (for SID/VIC-II rails, TOD clock, and User Port) to the C64, VIC-20 CR, and early Plus/4.

5-Pin Square DIN (Male Plug on PSU / Female Socket on Computer)

Side-by-side pinout for the 5-pin Square DIN used on BOTH the Flat Commodore 128 and the Amiga 500/600/1200 — and why you must NEVER swap their power bricks!

4-Pin Square DIN (Plus/4) & 5.5×2.1mm Barrel Jack (C16/C116/Spectrum)

Covers the Commodore Plus/4's 4-pin Square DIN (+5V DC + 9V AC) and the notorious 9V DC Centre-Negative barrel jack shared by the C16, C116, and ZX Spectrum 16K/48K/128K/+2.

5.5×2.1mm Barrel (+5V) + 3.5mm Mono Jack (+12V) & 6-Pin DIN (+2A/+3)

Covers the Amstrad CPC 464/6128's regulated +5V DC (centre-positive!) barrel jack, the CPC 6128's +12V DC 3.5mm mono jack, and the Amstrad ZX Spectrum +2A/+3 6-pin DIN power socket.

3-Pin Slotted Flat-Blade Receptacle (Proprietary Sinclair)

Carries unregulated +9V DC (for the internal 7805 heatsink regulator) and 15.6V AC (for the internal +12V / -12V rectifiers) into the Sinclair QL.

5-Pin DIN (180° on TRS-80 Model I; 240° on Dragon 32/64)

Covers the external multi-rail transformer bricks for the TRS-80 Model I (5-pin 180° DIN) and the Dragon 32 / Dragon 64 (5-pin 240° DIN).

7-Pin DIN (270° Circular — DIN 45329)

Pure +5.0V DC (1.5–2.0A) across three parallel power pins (Pins 1, 4, 6) and three parallel ground pins (Pins 2, 3, 5) for all Atari XL/XE computers (except 1200XL).

4-Pin Rectangular Socket (TI-99/4A) & Molex Motherboard Headers (A2000/3000/4000)

Covers the TI-99/4A's external 4-pin dual-AC (18V AC + 8.5V AC) socket and internal triple-rail harness, plus Big-Box Amiga ATX conversion wiring and the TICK clock.

9-Pin D-Sub Male on Computer (DE-9M / DB9)

The universal 9-pin D-Sub joystick, paddle, and mouse standard — plus the critical differences on Pin 5/7/9 across C64, Amiga, Amstrad CPC, and MSX!

8-Pin Circular Mini-DIN (Joystick) & 7-Pin Circular Mini-DIN (Cassette)

Adapter wiring to connect standard 9-pin Atari/C64 joysticks and C2N 1530 Datasettes to the Commodore Plus/4, C16, and C116.

5-Pin / 6-Pin 240° DIN (Joysticks) & 5-Pin 180° DIN (Cassette)

Covers the 100 kΩ potentiometer analogue joystick ports on the Dragon 32/64 (5-pin DIN) and CoCo 1/2/3 (6-pin DIN), plus the 5-pin DIN cassette port.

7-Pin 270° DIN (Oric) & 5-Pin 180° DIN (BBC Micro / Electron / CPC 6128)

One-stop reference for European 5-pin and 7-pin DIN cassette sockets (Oric-1/Atmos, BBC Micro, Acorn Electron, Amstrad CPC 6128, and MSX) — compatible with standard 5-pin plugs!

9-Pin D-Sub Male (Side Joystick Port) & 9-Pin D-Sub Female (Rear Cassette Port)

Explains why the TI-99/4A multiplexes BOTH Joystick 1 and Joystick 2 through a single 9-pin D-Sub port and how to wire a 10-diode Atari DB9 splitter.

2×6 (6-Position Double-Sided, 0.156" / 3.96mm Pitch) PCB Edge Finger

The 6-finger PCB edge connector used across the PET (two ports!), VIC-20, C64, and C128 for the 1530 C2N Datasette, Tapuino, and Tapecart.

2×12 (24-Contact Double-Sided, 0.156" / 3.96mm Pitch) PCB Edge Finger

Exposes an 8-bit bidirectional parallel port (PB0–PB7 from 6526 CIA #2 or 6522 VIA), RS-232 / Wi-Fi modem lines, PET CB2 audio, and +5V DC / 9V AC rails.

2×12 (24-Contact, 0.156" Pitch) Edge Finger on PET -> 24-Pin IEEE-488 / Centronics

High-speed 8-bit parallel IEEE-488 (GPIB) bus connecting Commodore PETs to 2031/4040/8050/8250 disk drives, printers, and modern PETdisk MAX / SD2PET emulators.

DB25 Female (Amiga/ST/PC), 34-Pin Edge (CPC) & 20/26-Pin IDC (BBC/Oric/Dragon)

Covers the DB25 parallel port on the Amiga and Atari ST (used for Plipbox Ethernet & Covox DACs!), the Amstrad CPC's 7-bit printer edge, and the 20/26-pin IDC headers on the BBC Micro, Oric, and Dragon.

6-Pin DIN (240° Circular — DIN 45322)

The 6-pin DIN daisy-chain disk/printer bus connecting the VIC-20, C64, C128, SX-64, C16, and Plus/4 to 1541/1571/1581 drives, SD2IEC, and Pi1541.

13-Pin Trapezoidal Two-Row Proprietary Socket (Male Pins on Atari)

Joe Decuir's precursor to USB — daisy-chains floppy drives (810/1050), cassette decks, printers, modems, and modern **FujiNet / SDrive-MAX** adapters at up to 125 kbps.

19-Pin D-Sub Female (ACSI DMA) & 14-Pin Circular DIN (External Floppy)

Covers the Atari ST's 19-pin ACSI 8-bit DMA hard disk bus (used by **UltraSatan** and **ACSI2STM**) and the 14-pin circular DIN external floppy drive port (Drive B:).

23-Pin D-Sub Female on Amiga (DB23F — Requires DB23 Male Plug on Cable)

Connects external 880 KB Amiga floppy drives (DF1:, DF2:, DF3:) and external Gotek emulators — supplying both signals AND +5V / +12V power over a 23-pin D-Sub.

34-Pin (2×17 0.1" IDC Ribbon) & 44-Pin (2×22 2.0mm Pitch 2.5" IDE)

The #1 floppy upgrade reference on the bench: compares true 34-pin Shugart (DS0 = Pin 10, Pin 34 = READY) against IBM PC twisted cables (DS1 = Pin 12, Pin 34 = Disk Change), plus the 26-pin Amstrad/Spectrum +3 ribbon and 44-pin Amiga IDE header.

2×22 (44-Pin Card Edge: 0.100" Pitch on C64/128/SX-64; 0.156" Pitch on VIC-20)

Full CPU address/data bus, /GAME & /EXROM Ultimax/8K/16K ROM banking, /IO1//IO2 ($DE00/$DF00), and /DMA on the C64/C128/SX-64 — plus the VIC-20's /RAM1–3 & /BLK1–5 44-pin slot.

2×28 Edge (ZX Spectrum), 2×25 Edge (Amstrad CPC) & 2×25 Slot (MSX)

Complete Z80 bus pinouts for the ZX Spectrum (2×28 edge with /ROMCS), Amstrad CPC (2×25 edge with /ROMDIS), and MSX (50-pin Cartridge Slot with /SLTSL and SW1/SW2).

34-Pin / 40-Pin 0.1" IDC Ribbon (BBC & Oric) & 50-Pin Card Slot (Apple II)

Covers the BBC Micro's 34-pin 1MHz Bus and 40-pin Tube co-processor port (PiTubeDirect), the Oric's 34-pin expansion port (/MAP & /ROMDIS for Erebus/Cumana), and the Apple II 50-pin Peripheral Slots.

25-Pin D-Sub (DB25) & 9-Pin D-Sub (DE-9)

Side-by-side DB25 and DE-9 RS-232 DTE pinouts plus the 7-wire hardware-handshaking Null-Modem cable schematic for Amiga Explorer, Kermit, and CP/M transfers.

9-Pin D-Sub (DE-9 — Non-Standard Pinout!) & 3.5mm Mono Jack (QL-NET)

Explains the Sinclair QL's non-standard SER1 (DCE) and SER2 (DTE) DE-9 serial ports — where **Pin 6 outputs +12 V DC** and **Pin 1 is GND**!

4-Pin Circular DIN (CoCo) & 5-Pin "Domino" DIN 41524 (BBC Micro RS-423)

Build a 3-wire DriveWire 4 virtual disk server cable for the Tandy CoCo 1/2/3 or a high-speed 19,200-baud RS-423 PC link cable for the Acorn BBC Micro!

5-Pin DIN (180° Circular — DIN 41524)

31,250-baud opto-isolated current-loop MIDI ports on every Atari ST — including Atari's clever hidden **MIDI THRU on Pins 1 & 3 of the MIDI OUT socket**!

24-Pin Reversible USB Type-C Receptacle (2×12 Dual Row)

The 24-pin reversible USB-C standard — including the mandatory **TWO separate 5.1 kΩ pull-down resistors on CC1 (A5) and CC2 (B5)** needed when converting retro computers to USB-C power!

8P8C Modular Plug / Jack (RJ45)

Standard T568B and T568A twisted-pair colour codes for 10/100Base-TX (Pins 1–2 & 3–6) and Gigabit Ethernet — used on Amiga Plipbox / PCMCIA, C64 RR-Net, and Apple II Uthernet II.

19-Pin HDMI Type A Receptacle

Complete 19-pin HDMI Type A reference for diagnosing no-signal issues on RGBtoHDMI, OSSC, RetroTINK, and Mini-HDMI console mods.

30-Pin / 38-Pin Dual-In-Line 0.1" Header (3.3 V CMOS Logic!)

The microcontroller behind **FujiNet, BlueRetro, Zimodem Wi-Fi Modems, and TRS-IO** — with critical 3.3 V level-shifting and boot-strapping pin warnings.