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5-14 Troubleshooting KPCI-PIO24 User’s Manual
Figure 5-6
Port A output settings, bit pattern 1
NOTE Note that the bit is ON when the switch button is DOWN.
10. Click the ‘Update All’ button on the PIO Control Panel.
11. Observe the PIO Control Panel DIP switches for ports B and C, which in this case monitor
bit patterns instead of set them. The bit patterns for ports A, B, and C should all be the same,
because the output bits of port A are connected to the corresponding input bits of ports B
and C. The PIO Control Panel example, Figure 5-3, shows the results of a successful loop-
back test for bit pattern 1.
• If the bit patterns for ports A, B, and C do not agree, the board is not functioning properly.
Stop here, and return to the step in the “General problem isolation procedure” where you
were directed to do I/O bit tests (step 17 or step 26e in the “General problem
isolation procedure”).
• If the bit patterns for ports A, B, and C do all agree, continue with step 12.
12. Using the DIP switch on the PIO Control Panel, set port A to the bit pattern 2, as shown in
Figure 5-7. Bit pattern 2 corresponds to a byte value of AA in hexadecimal.
Figure 5-7
Port A output settings, bit pattern 2
13. Click the ‘Update All’ button on the PIO Control Panel.
14. Again, observe the PIO Control Panel DIP switches for ports B and C. The bit patterns for
ports A, B, and C should again all be the same, as illustrated in Figure 5-8.
PORT A
7 6 5 4 3 2 1 0
n n n n
On
n n n n
&H55
PORT A
7 6 5 4 3 2 1 0
n n n n
On
n n n n
&HAA