
9. TROUBLESHOOTING
B--63005EN/02
664
A bus error occurred on the motherboard (main CPU board). This alarm
indicates that an error occurred during the exchange of data within the
motherboard (main CPU board).
Replace the CPU card on the motherboard (main CPU board).
Replace the display control card, axis control cards, DRAM module,
FROM module, and SRAM module, one at time.
Replace the motherboard (main CPU board).
If alarm 972 is issued, indicating on the screen that a BUS error occurred
on an option board, replace the CPU card on the option card, DRAM
module, axis control cards, and option card, one at a time.
Some option boards have a circuit equivalent to the CPU card installed
on the boards themselves. See the hardware chapter for details.
Screen display example
SYSTEM ALARM
972 NMI O CCURRED IN OTHER MODULE
SLOT 01
975 F-BUS ERROR <SUB
9.36
ALARM 975
(BUS ERROR)
Causes and actions
D Replacing the CPU card
D Replacing other cards
and modules
D Replacing the
motherboard (main CPU
board)
D BUS error on an option
board