Processor: | 68000@14Mhz |
FPU: | None |
MMU: | None |
Max Ram: | 8MB |
Ram Type: | DRAM Chips |
Plugs into the CPU socket of the A2000 or A500. The board takes either 256K*4 DRAMs 100ns or faster (eg SIEMENS HYB514256B) for a maximum of 2MB or 1MB*4 DRAMs preferably faster than 100ns (eg TOSHIBA TC514400P) for a maximum of 8MB of RAM. It possible to mix and match the two types, however it may not always work so some experimentation may be needed.
This card has 5 memory banks known as Shadow, Bank 0, Bank1, Bank2 and Bank3.
Mem Size | BANK 0 | BANK 1 | BANK 2 | BANK 3 | DIP 3-6 1 = ON, 0 = OFF (Ascending Order) |
1 MB | 4x256K*4 | 4x256K*4 | - | - | 0-1-1-1 |
2 MB | 4x256K*4 4x1M*4 |
4x256K*4 | 4x256K*4 | 4x256K*4 | 0-1-0-1 1-0-1-1 |
3 MB | 4x256K*4 | 4x256K*4 | 4x1M*4 | - | 0-1-1-0 |
4 MB | 4x1M*4 | 4x1M*4 | - | - | 0-0-1-1 |
5 MB | 4x256K*4 | 4x256K*4 | 4x1M*4 | 4x1M*4 | 0-1-0-0 |
6 MB | 4x1M*4 | - | 4x1M*4 | 4x1M*4 | 1-0-0-0 |
8 MB | 4x1M*4 | 4x1M*4 | 4x1M*4 | 4x1M*$ | 0-0-0-0 |
Note: For any empty memory banks, all DIP switches should be set to ON. A memory testing program was usually supplied with this board to test for defective memory, in order to use it DIP switch 2 must be set to on.Jumpers J1 and J2 are set at the factory and must not be changed. Pin1 of the jumpers are not clearly identifed, however both jumpers should have the two pins shorted that are farthest away from the J1/J2 labels. DIP Switch 1 is used to set the startup frequency of the card between 7Mhz and 14Mhz, you will have to experiment to find which setting of the DIP switch matches which frequency. All user settings are accomplished using the 6 dip switches. Shadow RAM can be used to softkick another another kickstart, including 3.1.
Thanks to Rainer Kraus, Ron Mascaro and Andreas C Schmidt.