The card requires a memory expansion connector found on the IIc logic board. Simply exchange a logic board that does not have the connector for a board with the connector.
The Memory Expansion Card is sold with 256K RAM and may be expanded to 512K, 768K, or 1 Megabyte of RAM. Additional memory may be added at any time by plugging 256K RAM increments into the board's sockets.
Note: The Memory Expansion Card is static sensitive, so that proper electrostatic discharge precautions must be taken before handling the card.
The Memory Expansion Card will be available under ProDOS as a RAM disk, with the name /RAM4. Some software, such as AppleWorks 2.0, will use the extra RAM within the program.
To test the Memory Expansion Card, power on the Apple IIc and follow these steps:
1. Simultaneously press CTRL and RESET
2. Type CALL -151(CR)
3. Type C40AG(CR)
The Apple IIc responds with a message that indicates the RAM size found (256, 512, 768K, or 1M) and then tests the card until an error or until you press ESC.
The Memory Expansion Card test on an Apple IIc will give results whether or not a card is actually installed. You must make sure that a card is properly installed before getting valid results from the test.
When you run the diagnostics and there is no card, you should see:
MEMORY CARD TEST
ESC TO EXIT
TEST WILL TAKE 180 SECONDS
CARD SIZE = 1 MEG
PASSES = 0000
CARD FAILED
ADDRESS ERROR
SEE DEALER FOR SERVICE
8002- M=00 A=04 X=C1 Y=A0 P=B0 S=CE
(M is the memory bank where failure occurred)
If this is the message you are getting, then you may not have a RAM card (or it may not have RAM in it).
There is no other way of determining how much memory the Apple IIc has without writing a machine language program.