Arcom SC88T, Technical Manual

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Link area 6 and 7 EPROM pins
Link area 8 and 9 RAM pins
Link area 10 Serial Input level on channel A
Note : This link is hardwired in the B position. You must take care if the A position is
used: If RS232 levels are input in the A position, SCC will be destroyed.
J90 SC88T
Page 12
2192-08819-000-000
+ LK6A
LK6B
+ LK7A
LK7B
EPROMs pin 1 to +5V (all except 27512)
EPROMs pin 1 to A15 (27512 only)
EPROMs pin 27 to +5V (2764 & 27128)
EPROMs pin 27 to A14 (27256 & 27512)
LK8A
+ LK8B
+ LK9A
LK9B
NB: LK9 Dependant on LK8
RAM power is from STEbus VSTBY line
RAM power is from on-board +5V
RAM pin 26 to +5V (8k RAMs or VSTBY)
RAM pin 26 to A13 (32k RAMs)
Figure 7.
Link areas 6
and 7
o o
7A 6A
o o
7B 6B
o o
Figure 8.
Link areas 8
and 9
o o
9A 8A
o o
9B 8B
o o
LK10A
+ LK10B
Serial input is at TTL levels
Serial input is at RS232 levels
Figure 9.
Link area 10
o
A
o
B
o