Hardware Diagnostic Facilities

Preamble

There are a few very low-level routines for circuit diagnostics. These live in the directory MAINT:

CLOF

Turns the clock off.

This is useful in that if data and address lines are being examined the processor is prevented from shooting off into the clock ISR which clutters things up.

DATATEST

Outputs a recognisable pattern on the data lines.

Pattern is a '1' followed by the data line number (4 bits) followed by another '1'. Actual pattern is a set of staircases but the data lines are readily identifiable.

IGRID

Puts a grid pattern up on the Level 2 graphics monitor

KEY

Reads the position of the mains switch/key.

PROCTEST

Stand-alone processor/memory test

BOOT PROCTEST.MOB

WOOF

Looks for a watchdog timer

Returns ``Passed'' if it found one, ``Hung up/Failed'' if it didn't.

view:hwdiag printed on 15/02/89 at 21.07

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