Diagnostics
Description of Tests
Description of Tests
ROM
This test checks the software data (engine, boot, and setups) stored in FlashROM on the Engine
Board.
A failure of this test may indicate a problem with the Flash ROM chip (U5 on the Engine Board),
associated circuitry, or the Engine Board.
Read-write
This test is a combination of the RAM, MABEL and LISA tests. The Read-write test writes data
to RAM and the MABEL and LISA registers then confirms that the data written can be read back
successfully.
A failure of this test indicates a problem with the Engine Board.
RAM
The RAM test writes to the microprocessor RAM space and verifies that the write was
successful.
A failure of this test may indicate a problem with the RAM or related circuitry on the Engine
Board.
MABEL
This test performs a read-write of the MABEL registers and verifies that the data written can be
read back successfully.
A failure of this test may indicate a problem with a MABEL, related circuitry or the Engine
Board.
LISA
This test confirms that the Lisa chip (U15) is properly installed and successfully interfacing with
the microprocessor.
A failure of this test indicates a problem with Lisa, related circuitry or the Engine Board.
Sound ROM
This test confirms that the Sound ROMs can be read by the MABELs by performing a checksum
of the Sound ROMs. The computed checksum is then compared to the stored checksum.
A failure of this test may indicate a problem with a Sound ROM (U19 or U20), or the Engine
Board.
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