Installation manual

Testing and Troubleshooting
If RAM in the text video page is bad or incomplete, you will see the message
“NO 80 COLUMN VIDEO AVAILABLE DUE TO INCOMPLETE
AUXILIARY MEMORY BANK 0” on the 40 column screen.
If there is no RAM failure, you will see eight repeated printings of the ASCII
character set in ascending numeric order on the 80-column screen. The inverse
ASCII character set is printed first, followed by the normal Set, each Set
repeated eight times. Check to see if there are any breaks in the character
pattern. Any breaks will indicate RAM failure. If a failure is suspected, run
the continuous RAM test to locate the bad chip.
Running A Test
Running the “quick”, “full”, or “continuous” tests shows a high resolution
picture of the MultiRam RGB Card. Each RAM socket is shown exactly as
laid out on the card.
Each socket is divided into four squares. Each socket is shown as four squares
because MultiRam RGB can contain Sixteen 64K auxiliary banks in its four
RAM groups. The Apple, through MultiRam RGB circuitry, addresses these
sixteen 64K banks as follows:
BANK A BANK B BANK C BANK D
0 1 2 3
4 7 A D
5 8 B E
6 9 C F
fly running any of these tests, you will see a spinning cursor appear in place
of the flashing cursor in the bottom four lines of the screen. The cursor will
spin until the test is completed.
You will also see four flashing lights blink off and on the left side of the
picture. These lights correspond to the flashing LED’s on the card and show
which of the sixteen banks of auxiliary 64K is being currently tested. Add
together the numbers that arc to the left of the lit LED’s to see which bank is
being tested. Auxiliary banks are tested from 15 to 0 in descending order.
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