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GILDERFLUKE & CO. ¥ 205 SOUTH FLOWER ST. ¥ BURBANK, CALIF. 91502-2102 ¥ 818/840-9484 ¥ FAX 818/840-9485
printed: February 27, 1999
Preliminary Instructions
for
Quad Piggyback Digital to Analog (D/A) Converter
The Quad Piggyback D/A converter is a small printed circuit card which can be
attached directly to any playback-only MICRO MACs ÔBrickÕ card. When installed, this card
converts all 4 eight bit channels on a brick to four separate analog outputs. Two of the
four output channels on the Brick cards J6 connector are taken over by the installation of
the Quad Piggyback D/A. Channels zero and one of the brick can still be used as
normally as digital outputs, but will carry the same data as is converted to an analog
signals on the Quad Piggyback D/A card. What would normally be used as channel two
of the Brick is used as a TTL level input for feeding test data into the Quad Piggyback D/A.
The 1/4 J6 which would normally be used as channel threeÕs output from the brick is
converted into a 1/4 J6/A output and carries all four of the analog output channels.
Installation:
1) Remove the fuse ÔF4Õ (the one closest to the edge of the card) from the MICRO MACs
card.
2) Bend down the end of the fuse holder which will come precariously close to the
Quad Piggyback D/A card when it is installed (or insulate this end of the fuse holder with
some double faced tape or similar material).
3) Remove the two ULN2803 chips from the two sockets near the large filter capacitor
(C1).
4) Plug the Quad Piggyback D/A converter into the two 18 pin sockets you removed
the ULN2803Õs from and the long single row header that runs down the center of the
board (JP-3).
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GILDERFLUKE & CO. ¥ 205 SOUTH FLOWER ST. ¥ BURBANK, CALIF. 91502-2102 ¥ 818/840-9484 ¥ FAX 818/840-9485
Outputs:
Note that only the second two channels of the J6 output gets changed by the
installation of a Quad Piggyback D/A card:
wire number color wire function
1 brown circuit ground
2 red channel 0 data bit 7
3 orange channel 0 data bit 6
4 yellow channel 0 data bit 5
5 green channel 0 data bit 4
6 blue channel 0 data bit 3
7 violet channel 0 data bit 2
8 gray channel 0 data bit 1
9 white channel 0 data bit 0
10 black +15 VDC unregulated power supply (fused for 1 amp)
11 brown circuit ground
12 red channel 1 data bit 7
13 orange channel 1 data bit 6
14 yellow channel 1 data bit 5
15 green channel 1 data bit 4
16 blue channel 1 data bit 3
17 violet channel 1 data bit 2
18 gray channel 1 data bit 1
19 white channel 1 data bit 0
20 black +15 VDC unregulated power supply (fused for 1 amp)
TTL level test data input:
21 brown circuit ground
22 red TTL LEVEL TEST DATA INPUT bit 7
23 orange TTL LEVEL TEST DATA INPUT bit 6
24 yellow TTL LEVEL TEST DATA INPUT bit 5
25 green TTL LEVEL TEST DATA INPUT bit 4
26 blue TTL LEVEL TEST DATA INPUT bit 3
27 violet TTL LEVEL TEST DATA INPUT bit 2
28 gray TTL LEVEL TEST DATA INPUT bit 1
29 white TTL LEVEL TEST DATA INPUT bit 0
30 black +15 VDC unregulated power supply
J6/A analog output:
31 brown circuit ground
32 red +15 VDC unregulated power supply
33 orange + channel 3 output data
34 yellow - channel 3 output reference
35 green + channel 2 output data
36 blue - channel 2 output reference
37 violet + channel 1 output data
38 gray - channel 1 output reference
39 white + channel 0 output data
40 black - channel 0 output reference
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