CompuServe Messages

FG >>purchased a secondhand Amiga 500 with Workbench 1.2 with no instruction book.<< The latest version of WB for the A500/2000 is version 2.1 of the system disks, and version 2.05 for the KickStart ROM. Both disks & ROM, are available in a single upgrade kit. A separate kit that contains only the 2.1 system disks for those that already had 2.04/2.05 ROMs which shipped with an earlier "2.04" disks. Version 3.0 (disks & 3.0 ROMs) is shipping with the A1200 & A4000, but is not available yet for older models. It is believed that "3.1" will be made available for the 500, 2000, & 3000 (RSN). — The maximun amount of memory you can add, depends on how you expand the system. With a 68000 CPU, the AmigaOS allows for 2-megs CHIP (graphic), and 8-megs FAST (system), plus 1.5-megs SLOW (FAST memory accessed thru the CHIP memory bus). Without hardware hacks, the A500 allows a total of 9-megs using a configuration of either: – 512K CHIP – 512K SLOW – 8-megs FAST or – 1024K CHIP – 8-megs FAST Hardware hacks using "sandwich" boards, (mini-boards that insert between chips and the motherboard), can allow the full 2-megs of CHIP memory to be added, and the 1.5-megs of SLOW memory for a possible of 11.5-megs of memory. As for standard hardware: The A500 has 512K of "shared" graphics/system (CHIP) memory on the motherboard. As is, the belly slot (A501-slot), allows for another 512K of system (SLOW) memory, but can be re-configured as CHIP memory by upgrading the Agnus chip, and cutting some jumpers. The 86-pin Expansion of the left side of the Amiga, can be used to add upto 8-megs of FAST memory. If special third party hardware is used: A possible 4-megs can be added internally in the A501-Slot. This option not only uses a A501-card, but a "sandwich" board that inserts under the Gary chip, and runs a ribbon cable to the card to provide extra support lines. However, this option can limit the amount of FAST RAM that can be added on the 86-pin Expansion bus, and althought it as mapped into memory as FAST RAM, it still is on the CHIP bus (making it SLOW memory.) A sandwich board that inserts under the Agnus chip can allow upto 2-megs of CHIP memory. This option requires a version of the Agnus that was designed to access the 2-megs of CHIP memory. – Ron. – ap'ing with AP. (Eagles may fly, but weasels aren't sucked into jet engines.)