9 PIN D-SUB FEMALE at the Monitor
The Commodore 1084D and 1084DS monitors accept video input through a single 9-pin D-Sub female connector that operates in either analog RGB or digital RGBI (TTL) mode, selected by the signal present. This design distinguishes the 1084D and 1084DS from the earlier 1084 and 1084S models, which used separate 6-pin DIN and 8-pin DIN connectors for the two modes. The connector is compatible with the analog RGB output of Amiga computers (via an appropriate cable from the Amiga’s DB-23 video port) as well as with TTL RGBI sources such as the Commodore 128’s 80-column output. In analog mode, composite sync is carried on pin 7; in digital mode, pin 7 is unused and separate horizontal and vertical sync signals appear on pins 8 and 9.
| Pin | Name | Analog Mode | Digital Mode |
|---|---|---|---|
| 1 | GND | Ground | Ground |
| 2 | GND | Ground | Ground |
| 3 | R | Red | Red |
| 4 | G | Green | Green |
| 5 | B | Blue | Blue |
| 6 | I | n/c | Intensity |
| 7 | CSYNS | Composite Sync | n/c |
| 8 | HSYNC | n/c | Horizontal Sync |
| 9 | VSYNC | n/c | Vertical Sync |
Notes
- The connector at the monitor is a 9-pin D-Sub female (DE-9F); the cable plug from the computer is male. The SVG illustration shows a male connector for reference.
- Mode selection (analog vs. digital) is determined by the monitor’s front-panel input switch or by the signal type detected; both modes share the same physical connector.
- Analog RGB input impedance is 75 ohm; digital RGBI inputs are TTL-level.
- The 1084D and 1084DS differ from the 1084 and 1084S, which provide separate 6-pin DIN (analog RGB) and 8-pin DIN (digital RGBI) inputs rather than this combined DE-9 connector.
Signals
- GND — Signal ground; two pins (1 and 2) are both grounded.
- R — Red video signal; analog 0–0.7 V P-P at 75 ohm in analog mode, TTL logic level in digital mode.
- G — Green video signal; same electrical characteristics as R.
- B — Blue video signal; same electrical characteristics as R.
- I — Intensity (digital mode only); TTL signal that boosts all three colour channels to produce the bright set of 8 colours in a 16-colour RGBI palette. Not connected in analog mode.
- CSYNS — Composite sync (analog mode only); combines horizontal and vertical sync on a single line. Not connected in digital mode.
- HSYNC — Horizontal sync (digital mode only); TTL-level line sync pulse. Not connected in analog mode.
- VSYNC — Vertical sync (digital mode only); TTL-level frame sync pulse. Not connected in analog mode.