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SCART RGB AV Dongle
The SCART RGB A/V dongle provides RGB video and audio output directly to any SCART-compatible display. It connects to the PICO9918 via the FFC connector available on v1.2+ boards.
When fitted, the SCART dongle is automatically detected by the PICO9918 and outputs a clean RGB PAL 576i @ 50 Hz signal by default. NTSC 480i @ 60 Hz output is also supported. See SCART Output Reference for timing details and build flags.
The auto-detection only occurs on first power-up. If the dongle is swapped while the PICO9918 is powered, the output signals will not change.
Important
Requires PICO9918 firmware v1.2.0 or newer - that is the release which added the SCART mode setting.
The SCART RGB A/V dongle is compatible with all FFC-equipped PICO9918 boards:
- PICO9918 PRO v2.0
- PICO9918 v1.3
- PICO9918 v1.2
- PICO9918 SCART RGB A/V dongle
- 2-pin audio lead + header
An FFC cable and the SCART cable itself are not included. See below.
The dongle connects to the PICO9918 via a 12-pin 0.5 mm pitch FFC cable (same cable used by the Digital AV Dongle and VGA dongle). If you already have one fitted, it can be reused. FFC cables are available as an option when purchasing.
See Hardware Setup for detailed cable connection instructions.
The dongle includes a 2-pin JST lead which carries mono audio from the host system's mainboard through to the SCART output. The matching 2-pin header is included for soldering to the host board.
Audio does not travel over the FFC cable. The 12-way FFC carries video only, so the audio lead is a second, separate connection from the host mainboard to the dongle's 2-pin AUDIO header, bypassing the PICO9918 altogether. The SCART dongle is passive, so the lead goes straight to Mini-DIN pins 2 and 3, which the cable takes to SCART pins 2 and 6.
| System | Wiring Guide |
|---|---|
| TI-99/4A | HDMI Dongle Audio Wiring (same audio tap point as the HDMI dongle) |
If the audio lead is left disconnected the video signal still works normally; only the audio pins on the SCART connector will be silent.
The dongle's Mini-DIN output follows the standard Sega Saturn RGB SCART pinout, so an off-the-shelf Saturn SCART cable works unmodified. The signals below come from the dongle's own schematic (pcb/scart/pico9918_scart_v1_3.pdf).
| Mini-DIN Pin | Dongle Signal | SCART Pin |
|---|---|---|
| 1 | (unused) | - |
| 2 | Audio | 2 |
| 3 | Audio | 6 |
| 4 | +5 V | 8, and 16 via 180 Ω |
| 5 | Red | 15 |
| 6 | Green | 11 |
| 7 | Blue | 7 |
| 8 | Composite sync | 20 |
| 9 | (unused) | - |
| 10 | (unused) | - |
| Shell | Ground | 4 / 5 / 9 / 13 / 17 / 18 / 21 |
Note
Mini-DIN pins 2 and 3 are the same net on the dongle. The 2-pin audio lead carries a single mono channel, fanned out to both pins so it reaches both channels of a stereo SCART display.
Composite sync is driven on pin 8 and fed to SCART pin 20 by the cable. The dongle itself is passive - the only component on it besides the connectors is the 1 k detect resistor - so RGB blanking through sync and the back porch is done by the firmware. See Line Timing.
The 180 Ω resistor to SCART pin 16 (RGB select) lives in the cable, not the dongle. There is no such part on the dongle's bill of materials. A ready-made Saturn SCART cable already has it; a hand-made cable needs it, or the display will show the composite signal on pin 20 instead of RGB.
If you are building a cable rather than buying one, this Saturn → SCART wiring diagram shows the whole run end to end, grounds and the 180 Ω to pin 16 included. It agrees with the table above.
Video and audio exit the dongle via a 10-pin Mini-DIN socket that matches the pinout used by the Sega Saturn SCART cable. These cables are readily available from retro gaming suppliers and online marketplaces.
Plug the Mini-DIN end into the dongle and the SCART end into your display or upscaler.
- Fit an FFC cable between the PICO9918's FFC connector and the SCART dongle. See Hardware Setup.
- Solder the supplied 2-pin header to the audio tap point on your host system's mainboard and plug in the audio lead (optional, video works without this).
- Connect a Sega Saturn SCART cable from the dongle's 10-pin Mini-DIN socket to your SCART display or upscaler.
- Power on. The PICO9918 will detect the dongle and switch to SCART RGBs output automatically.
| Region | Default Output |
|---|---|
| PAL | 720×576i @ 50 Hz |
| NTSC | 720×480i @ 60 Hz |
Both modes are interlaced RGBs at a 13.5 MHz pixel clock. For full timing, voltage levels, sync pulse structure and build flags, see SCART Output Reference.
- Dongles: all three dongles compared, and the FFC pinout they share
- SCART Output Reference: PAL/NTSC timing and voltage specifications
- Digital AV Dongle: HDMI alternative
- Hardware Setup: FFC cable routing