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Posted Sat Jan 19, 2019 11:53 PM
Posted Sun Jan 20, 2019 3:58 AM
When I first got the 5150 it had the AST SixPack Plus adapter installed with 1 bank and the computer reported 128k memory.
It is a PC1 motherboard and all memory banks are full.
With the AST SixPack Plus adapter installed I got 128k.
If all the banks on the main board are full, you should be starting at 256K (S1 off, S2 on, S3 on).
The SixPack Plus was set to start at 64k (dip switches 1,2,3 are off)
SW2 is almost certainly set for a total of 128K. So that is all that the BIOS is ever going to look for, and what it's going to report as the memory size.
I then tried the following AST dip switch configurations per the users manual:
- AST 4,5 off 6 on – bank 1 only active (bank 1 and 2 populated), no boot error, 131,072 bytes free
- AST 4,6 off, 5 on – bank 1-2 active with 2 banks memory, no boot error 131,072 bytes
- AST 4,6 off, 5 on – bank 1-2 active with 2 banks memory, no boot error 131,072 bytes (same as previous but swapped with different memory)
- AST 4, off, 5-6 on – bank 1-3 active with 3 banks memory, no boot error 131,072
Posted Sun Jan 20, 2019 4:30 AM
And looking over the BIOS listings, it's as you might guess: If SW1 specifies less than 64K, then BIOS completely ignores the contents of SW2. Otherwise it adds the value of SW2 (1-5) in 32K increments to the 64K that is already specified by SW1 pins 3,4. So most likely what you have for getting 128K total is SW1 = off, off SW2 = off, off, off, on, off. For 256K, SW2 should be off, off, on, on, off.
Posted Mon Jan 21, 2019 12:46 AM
Thanks for all the information! I got everything to work now!
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