Mackie d8b v3, Service Manual

Page: 21 / 117

21
DSP SIGNAL FLOW
DT4
DT3
DT2
DT1
DT4
DT3
DT2
DT1
23 AND 24
21 AND 22
19 AND 20
17 AND 18
15 AND 16
13 AND 14
11 AND 12
9 AND 10
7 AND 8
5 AND 6
3 AND 4
1 AND 2
J20-7,56
J20-5,58
J20-3,60
J20-1,62
J19-7,56
J19-5,58
J19-3,60
J19-1,62
J18-7,56
J18-5,58
J18-3,60
J18-1,62
J47-14
J47-10
J47-6
J47-2
J47-31
J47-27
J47-23
J47-19
J48-14
J48-10
J48-6
J48-2
DT4
DT3
DT2
DT1
DT_8
DIGITAL SIG
NAME ON
TAPE BOARD
ANALOG
TAPE OUTPUT
PAIRS
ANALOG
TAPE INPUT
PAIRS
BACKPLANE
TO DSP
CONNECTOR
AND PIN NO.
CARD TO
BACKPLANE
CONNECTOR
AND PIN NO.
WHAT THE SIGNAL
IS CALLED ON
THE BACKPLANE
AND DSP BOARD
DT_6
DT_4
DT_2
DT_16
DT_14
DT_12
DT_10
DT_24
DT_22
DT_20
DT_18
23 AND 24
21 AND 22
19 AND 20
17 AND 18
15 AND 16
13 AND 14
11 AND 12
9 AND 10
7 AND 8
5 AND 6
3 AND 4
1 AND 2
DIGITAL SIG
NAME ON
TAPE BOARD
BACKPLANE
TO DSP
CONNECTOR
AND PIN NO.
CARD TO
BACKPLANE
CONNECTOR
AND PIN NO.
WHAT THE SIGNAL
IS CALLED ON
THE BACKPLANE
AND DSP BOARD
DR4 DR0_U16
DR3 DR0_U15
DR2 DR0_U14
DR1 DR0_U13
J20-8,55
J20-6,57
J20-4,59
J20-2,61
DR4
DR3
DR2
DR1
DR0_U20
DR0_U19
DR0_U18
DR0_U17
J19-8,55
J19-6,57
J19-4,59
J19-2,61
DR4
DR3
DR2
DR1
DR0_U24
DR0_U23
DR0_U22
DR0_U21
J18-8,55
J18-6,57
J18-4,59
J18-2,61
J47-16
J47-12
J47-8
J47-4
J47-33
J47-29
J47-25
J47-21
J48-16
J48-12
J48-8
J48-4
These are the signals
transmitted to the DSP
board from the Tape
inputs.
What happens is this:
Two analog signals are
converted into digital and
combined into one digital
signal.
For example, analog
signals 23 and 24 (from the
DB25 pin connector on the
rear panel) are converted
and combined to create a
digital signal DR4 on the
tape card. This is then
given a new name of
DRO_U16 and sent to the
DSP board using connec-
tor J47, pin 16.
TAPE CARDS continued
NOTE: All three tape cards
are identical, and the
difference in signal name
comes from where each
card is fitted in the
backplane slots. If a card is
fitted into slot 1-8, it
connects to the
backplane’s J18 and so for
example, the card’s DT2
becomes DT_20 on the
backplane and DSP board.
If the card is in the 9-17
slot, it uses J19 and so the
card’s DT2 becomes
DT_12.