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The 4MEM board can provide LIM EMS 3.2 for ECB based CPU boards.
Perhaps the 4MEM circuit can be adapted for a plug-in board for the
8088 motherboard. The driver is in Board Information \ ECB Processor Boards \ ECB SBC-188 \ BIOS039.ZIP \\ file EMM4MEM.SYS (EMM4MEM.ASM). --John On 10/02/2012 08:37 AM, Sergey wrote: LIM EMS - should be possible to design one. The simplest implementation would have a single 16 KiB window, and implementation will be very similar to paged RAM/ROM implementation in N8VEM SBC: - Some SRAM, e.g. 4 or 8 512KiB chips - Map register(s) that provide top address bits (A14-A21) - Address decode logic - for SRAM and for the map register(s), can be implemented using 74LS688 or similar ICs. For SRAM it also will need to include chip select logic, something like 74LS138 decoder. |