Specifications

CHAPTER 3
I/O Specifications
Audio Connectors 47
Figure 3-1 on page 34 and Figure 3-2 on page 35 show the location of this connector on
the 12" and 7" cards, respectively. “GIMO Support for Video Output” on page 28
provides more information about this type of interface.
Table 3-6 shows the pin assignments for the GIMO 16-pin connector, Molex part number
87256-1641, or AMP part number 104338-3. The connector is at location J11 on the
12" card and J4 on the 7” card. The pin assignments are the same for each card.
Audio Connectors 3
In most CPUs, audio input and output are provided by two identical four-wire ribbon
cables. The audio input cable routes sound inputs to the 12" or 7" card from a sound
source such as a CD player. The cards have a Sound Blaster–compatible audio system,
and the audio output cable routes sound to the Macintosh sound system, speakers, or an
external audio jack. Figure 2-9 on page 30 shows how the audio connections are made.
Note
In those CPUs that do not have discrete audio connectors, audio I/O is
implemented by means of a ribbon cable and the GIMO connector. ◆
Table 3-6 GIMO connector pin assignments
Pin number Signal Description
1, 9, 13 GND Ground
2 IREF Refresh
3 VSYNC Vertical synchronize
4 HSYNC Horizontal synchronize
5 RGB SEL(0) RGB select 0
6 VGA CSYNC VGA contrast synchronize
7 +5 V +5 V power supply
8 GIMO BLUE GIMO blue
10 GIMO GREEN GIMO green
11 GIMO DET L GIMO detect
12 GIMO RED GIMO red
14 GIMO OUTL GIMO sound output left
15 GIMO GND GIMO ground
16 GIMO OUTR GIMO sound output right