HP 16500B User Manual
Page 71
Disk Drive Voltages
Pin
Signal Description
Pin
Signal Description
Pin
Signal Description
1
Reset
15
Data
29
+5 V
2
Ground
16
Data
30
Ground
3
Data
17
Data
31
Interrupt Request
4
Data
18
Data
32
NC
5
Data
19
Ground
33
Address
6
Data
20
(connector key pin)
34
NC
7
Data
21
NC
35
Address
8
Data
22
Ground
36
Address
9
Data
23
Write Strobe
37
Register Select
10
Data
24
Ground
38
Register Select
11
Data
25
Read Strobe
39
NC
12
Data
26
Ground
40
Ground
13
Data
27
I/O Cycle Extend
14
Data
28
NC
7
If the hard disk drive signals appear as indicated, then the hard disk drive should be
replaced. If the signals do not appear, then either the data cable or the CPU board is
suspect. J12 of the CPU board can be probed in the same manner as described
above to check for the same signals.
8
Select Stop, and turn off the mainframe. Remove the power cable and replace the
faulty assembly.
9
Reassemble the mainframe.
Troubleshooting
To test the hard disk drive voltages
5–28