Chapter 3 Level 0 Diagnostics; Memory Test - NCR PC4i Service Manual

This chapter details the tests that are performed
during the
diagnostic routines that are contained in the ROM of
the NCR Personal Computer. These diagnostics are
initiated before any other activity is attempted each
time the computer is turned on.
Normal messages and error messages which may be
displayed on the screen are shown. Error codes which
are issued via the
parallel port are also listed. These error codes are
shown if the screen error messages are not displayed
because of malfunction.
The action to take for each specific error condition
is suggested.
It is recommended to log all tests that are running
as soon as the computer is switched on.

MEMORY TEST

Each time the power is turned on, the ROM program
performs a self-diagnosis that includes a check of
the Dynamic Random Access Memory (DRAM) resident on
the MPB and on the memory expansion board if present.
Other MPB components
tested. The following occurrences are normal:
A whirring motor noise
1.
heard .
A blinking cursor appears on the screen.
2.
The m e m o r y
3.
increments.
execution
M a i n
test
Level 0 Diagnostics
of the automatic power-on
P r o c e s s o r Board
and the keyboard are also
from the disk drive is
is c onducted
Chapter 3
(MPB)
KB
in 64
3-1