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41 lines
1.6 KiB
41 lines
1.6 KiB
ZRC has no real ROM. It has a single 2048K RAM chip. There
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are two startup modes supported by RomWBW.
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The normal startup mode treats the first 512KB like ROM and the
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remaining 1536KB as RAM. The first 512KB (pseudo-ROM) must be preloaded
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by the ZRC CF Loader. This mode simulates a normal ROM-based RomWBW
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startup.
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Bank Contents Description
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---- -------- -----------
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0x0 BOOT Boot Bank (HBIOS image) +
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0x1 IMG0 ROM Loader, Monitor, ROM OSes |
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0x2 IMG1 ROM Applications | Pseudo-ROM
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0x3 IMG2 Reserved |
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0x4-0xF ROMD ROM Disk Banks +
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0x10 BIOS HBIOS Bank (operating)
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0x11-0x3B RAMD RAM Disk Banks
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0x3C BUF OS Buffers (CP/M3)
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0x3D AUX Aux Bank (CP/M 3, BPBIOS, etc.)
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0x3E USR User Bank (CP/M TPA, etc.)
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0x3F COM Common Bank, Upper 32KB
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The ROMless startup mode treats the entire 2048KB as RAM. However, in
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this mode, only the first 512KB of RAM is utilized. This is because
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the RAM Disk is seeded by the CF Loader which is currently constrained
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to loading 512KB. The entire 512KB of RAM (less the top 32KB) must be
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preloaded by the ZRC CF Loader. There will be no ROM disk available
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under RomWBW. There will be a RAM Disk and it's initial contents will
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be seeded by the image loaded by the CF Loader.
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Bank Contents Description
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-------- -------- -----------
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0x0 BIOS HBIOS Bank (operating)
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0x1 IMG0 ROM Loader, Monitor, ROM OSes
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0x2 IMG1 ROM Applications
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0x3 IMG2 Reserved
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0x4-0xB RAMD RAM Disk Banks
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0xC BUF OS Buffers (CP/M3)
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0xD AUX Aux Bank (CP/M 3, BPBIOS, etc.)
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0xE USR User Bank (CP/M TPA, etc.)
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0xF COM Common Bank, Upper 32KB
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