5-12
5.6.3 Digital board checks
Table 5-4 summarizes checks for the digital board.
Drawing reference: Digital board; 6517-140
Table 5-4
Digital board checks
Step Item/component
Required condition
Remarks
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
Power-on test
U635 pin 16
U635 pin 32
U631 pin 92
U631 pins 1-24
U631 pins 31-48
U631 pin 101
U639 pin 1
U640 pin 1
U641 pin 13
U641 pin 14
U622 pins 34-42
U622 pins 26-31
U622 pin 24
U622 pin 25
U614 pin 7
U614 pin 9
U614 pin 5
U614 pin 12
U614 pin 18
U642 pin 3
U629 pin 3
U628 pin 7
RAM OK, ROM OK.
Digital common.
+5V
Low on power-up, then goes high.
Check for stuck bits.
Check for stuck bits.
16MHz clock
+3V
32.768kHz clock
Pulse train during RS-232 I/O.
Pulse train during RS-232 I/O.
Pulse train during IEEE-488 I/O.
Pulses during IEEE-488 I/O.
Low with remote enabled.
Low during interface clear.
Pulse train.
Pulse train.
Pulse train.
Pulse train.
Pulse train.
+5V, ±5%
+5V, ±5%
60Hz square wave.
Verify that RAM and ROM are functional.
All signals referenced to digital common.
Digital logic supply.
MPU RESET line.
MPU address bus.
MPU data bus.
MPU clock.
Backup battery voltage.
Serial RAM clock.
RS-232 RX line.
RS-232 TX line.
IEEE-488 data bus.
IEEE-488 command lines.
IEEE-488 REN line.
IEEE-488 IFC line.
ODATA line.
DCLK line.
A/D_TRIG line.
A/D_TRIG line.
A/D_STB line.
+5V3 supply.
+5V supply.
LINEFREQ signal.