The AHA-1740A/1742A/1744 executes a self-test diagnostics when the system power is turned on or after a Hard Reset. The self-test diagnostics tests the CPU operation, performs a check- sum test on the EPROM and checks the data transfer paths on the host adapter. The host system diagnostics may perform a more extensive
diagnostics by reading and writing data to memory.
Determining Problems Using the LED
The red Light-Emitting Diode (LED) on the host adapter indi- cates the result of the self-test diagnostic. When the power is first applied to the host adapter, the LED is turned on. Under normal operation the LED turns off when the self-test diagnostics is complete. The LED remains off until the host initiates activity on the SCSI bus or I/O port. If the self-test diagnostics fails the LED will flash a code indicating the type of test failure. The LED will flash once, twice (in rapid succession) or three times (in rapid succession) followed by a longer pause to indicate the type of test failure. The flash code is repeated continuously until the host adapter is powered-off, reset, or repaired.
If you are running the self-test diagnostic for fault-isolation pur- poses disconnect the SCSI interface cable. However, ensure that at least one set of SCSI terminators are installed on the last SCSI device. If the SCSI terminators are not present the LED remains on; indicating that the AHA-1740A/1742A/1744 is receiving an active RST signal. Continuous execution of the self-test diagnos- tics on the AHA-1740A/1742A can be enabled by inserting the diagnostic jumper pair on pin 4 of jumper 6. For the AHA-1744 in- sert the jumper pair on pin 4 of jumper 5.
