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Amiga Technical References
Supra 500XP:Inserting RAM Chips:
The SupraDrive 500XP is designed to use two
different kinds of memory chips of expansion. Using 256k x 4 DRAMs (1 megabit),
you can configure the 500XP with 512k, 1 meg, or 2 meg of RAM. For expansion
above 2 meg, you must use all 1 megabit x 4 DRAMs (4 megabit) on the 500XP
board. These DRAMs allow 2 meg, 4 meg and 8 meg configurations.
Up To 2 Meg with 256k x 4 DRAM DIPs
The RAM used for 512k, 1 meg
and 2 meg configurations must be 256k x 4 DRAM (DIP) chips, 120ns or faster. For
512k you'll need 4 chips; for 1 megabyte, you'll need 8 chips; and for 2
megabytes, you'll need 16 chips.
The RAM chips are inserted in the sockets towards the front of the 500XP. (Be sure to place each RAM chip so that its nothced or indented end, pin 1, is away from the LEDs) To install 512k, insert the four chips in the sockets next to the 512k labels. To install 1 megabyte, full all 8 sockets next to the 512k labels and the 1MB labels. To install 2 megabytes, fill all 16 sockets.
After inserting the RAM chips, following the instructions under SETTINGS RAM SIZE JUMPERS.
2 Megabytes or More with 1 Megabit x 4 DRAM DIPs
For 2, 4 or 8
megabytes RAM configurations, the 500XP is designed to accept - directly on the
board - 1 megabit x 4 DRAM chips (4 megabit) in a 300mil DIP package.
The DIP RAM used for 2 meg, 4 meg and 8 meg configurations must be 1 megabit x 4 DRAM (DIP) chips, 120ns or faster. FOr 2 megabytes you'll need 4 chips; for 4 megabytes, you'll need 8 chips, and for 8 megabytes you'll need 16 chips.
The RAM chips are inserted in the sockets towards the front of the SupraDrive (Be sure to place each RAM chips so that its notched or indented end (pin 1) is away from the LEDs) To Install 2 megabytes, insert the four chips in the sockets next to the 512K labels, just like the 1 megabyte configuration shown in the previous section. To install 4 megabytes, fill all 8 sokcets next to the 512K labels and the 1MB labels. To install 8 megabytes, fill all 16 sockets.
After inserting the RAM chips, follow the instructions under SETTINGS RAM SIZE JUMPERS.
2 Megabytes of RAM or More with 1 megabit x 4 DRAM ZIPs
To allow
you to use ZIP package DRAM, Supra has designed an add-on board that simply
adapts the 500XP sockets to accept ZIP chips. We have pretty much NEVER seen
this board, so don't worry about it. If you do require information for it, email
National Amiga.
Setting RAM Size Jumpers:
| Total RAM in 500XP | J1 | J2 | J3 |
| 0 meg | OFF | OFF | OFF |
| 512k | OFF | ON | ON |
| 1 megabyte | OFF | ON | OFF |
| 2 megabytes (256k x 1 DRAM) |
OFF | OFF | ON |
| 2 megabytes (1M x 4 DRAM) |
ON | OFF | ON |
| 4 megabytes | ON | OFF | OFF |
| 8 megabytes | ON | ON | ON |
To Set the SCSI Device Number of the Supra500XP Iteself:
You normally should not change this beyond the default of 7. But just in case, here's how:
| SCSI #0 | SCSI #1 | SCSI #2 | SCSI #3 | SCSI #4 | SCSI #5 | SCSI #6 | SCSI #7 |
| down | UP | down | UP | down | UP | down | do not use this |
| down | down | UP | UP | down | down | UP | do not use this |
| down | down | down | down | UP | UP | UP | do not use this |