The Apple Digital Video Application (DVA) connector is a 34-pin internal flat-ribbon connector that carries digitised YUV video data and analogue audio to an expansion card seated in the LC-type expansion slot. It was introduced with the Quadra 630 and LC 630 in 1994 and was also used on the Power Macintosh 5200 and 6200. The DVA interface is a functional subset of the later 60-pin DAV (Digital Audio Video) connector found on the Power Macintosh AV series (7200/7500/8500/9500); Apple supplied an adapter cable allowing DVA-compatible expansion cards to connect to the 60-pin DAV header on those later machines. The video data bus carries 8-bit luminance (Y, pins 1–8) and 8-bit chrominance (UV, pins 9–16) alongside timing signals and analogue audio lines.
| Pin | Description |
|---|---|
| 1 | Y bit 7 |
| 2 | Y bit 6 |
| 3 | Y bit 5 |
| 4 | Y bit 4 |
| 5 | Y bit 3 |
| 6 | Y bit 2 |
| 7 | Y bit 1 |
| 8 | Y bit 0 |
| 9 | UV bit 7 |
| 10 | UV bit 6 |
| 11 | UV bit 5 |
| 12 | UV bit 4 |
| 13 | UV bit 3 |
| 14 | UV bit 2 |
| 15 | UV bit 1 |
| 16 | UV bit 0 |
| 17 | Ground |
| 18 | Line-locked clock (LLC) in |
| 19 | Ground |
| 20 | Clock reference (CREF) in |
| 21 | Ground |
| 22 | Vertical sync (VS) In |
| 23 | Ground |
| 24 | Horizontal Sync (HS) In |
| 25 | Ground |
| 26 | Horizontal Reference Signal (HREF) In |
| 27 | Ground |
| 28 | YUV Direction Signal (DIR) |
| 29 | Ground |
| 30 | Reserved |
| 31 | Ground |
| 32 | Analog audio input left |
| 33 | Analog audio input common |
| 34 | Analog audio input right |
Notes
- The DVA connector is an internal header; it is not accessible from the rear panel of the machine.
- The interface provides access to the video digitiser IC’s YUV data bus at 4:2:2 format, allowing a card in the LC expansion slot to capture or process video frames.
- The DVA connector is a functional subset of the 60-pin DAV connector used on the Power Macintosh AV series. Apple provided an adapter cable so that DVA-compatible expansion cards could connect to the later 60-pin DAV header.
- Pins 17, 19, 21, 23, 25, 27, 29, and 31 are all ground returns; they interleave the signal lines to reduce crosstalk on the flat-ribbon cable.
- Pin 30 is reserved and should remain unconnected on expansion cards.
Signals
- Y bit 7–0 (pins 1–8) — 8-bit digitised luminance data bus, bit 7 (MSB) on pin 1
- UV bit 7–0 (pins 9–16) — 8-bit digitised chrominance data bus, bit 7 (MSB) on pin 9; carries multiplexed U and V components in 4:2:2 YUV format
- Ground (pins 17, 19, 21, 23, 25, 27, 29, 31) — signal ground returns
- LLC in (pin 18) — line-locked clock input; pixel clock derived from and phase-locked to the incoming video signal
- CREF in (pin 20) — clock reference input; provides the colour subcarrier reference frequency to the video digitiser
- VS in (pin 22) — vertical sync input from the video digitiser IC
- HS in (pin 24) — horizontal sync input from the video digitiser IC
- HREF in (pin 26) — horizontal reference signal input; indicates the active video line period
- DIR (pin 28) — YUV direction signal; controls the direction of the video data bus (input or output)
- Reserved (pin 30) — reserved; leave unconnected
- Analog audio input left (pin 32) — left-channel analogue audio input
- Analog audio input common (pin 33) — analogue audio ground/common return
- Analog audio input right (pin 34) — right-channel analogue audio input
References
- Macintosh Quadra 630 / LC 630 Developer Note — Apple Computer, Inc., Developer Technical Publications (1994); documents the 34-pin DVA digital-video expansion connector.