• Adjust the variable resister until the two color bars are
identical.
5. Once adjusted, reassemble the 800 Console and proceed to the RAM
Test. If unable to adjust the color bars refer to paragraph 5.4,
Troubleshooting.
Figure 5-6. 400 Console Color Adjustment
RAM TEST
The RAM Test utilizes six different tests to verify the operation of
the RAM Memory boards. The RAM Test checks the RAM memory in 8K
blocks. The number of 8K blocks is entered as part of the command
sequence. If you enter a number indicating less memory than actually
installed the diagnostic program will only check the memory
indicated. A maximum of 32K of RAM memory can be checked. In order to
check additional memory it will be necessary to swap tested memory
with untested memory.
Before running the RAM Test it is necessary to determine the type of
display format and mode for the test. Default setting for the display
format is a PASS/FAIL indication. Default setting for the test mode
is a single test. RAM Memory boards should pass three complete series
of diagnostic tests before acceptance. Typically a RAM Test is run as
follows :
ATARI Personal Computers 5-13