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Enhances memory map fidelity to allow for ROM holes on the Mac Plus.

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This is how the ROM detects the difference between the Plus and the 512ke, it seems.
This commit is contained in:
Thomas Harte 2019-08-10 23:53:34 -04:00
parent 4859d3781b
commit bbd4e4d3dc
1 changed files with 20 additions and 19 deletions
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39
Machines/Apple/Macintosh/Macintosh.cpp
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@ -182,7 +182,9 @@ template <Analyser::Static::Macintosh::Target::Model model> class ConcreteMachin
// Grab the word-precision address being accessed.
uint16_t *memory_base = nullptr;
HalfCycles delay;
switch(memory_map_[word_address >> 18]) {
switch(memory_map_[word_address >> 16]) {
case BusDevice::SCSI:
printf("SCSI\n");
default: assert(false);
case BusDevice::Unassigned:
@ -352,8 +354,8 @@ template <Analyser::Static::Macintosh::Target::Model model> class ConcreteMachin
// Addresses up to $80 0000 aren't affected by this bit.
if(rom_is_overlay) {
// Up to $60 0000 mirrors of the ROM alternate with unassigned areas every $10 0000 byes.
for(int c = 0; c <= 0x600000; c += 0x100000) {
map_to(c, ((c >> 20)&1) ? BusDevice::ROM : BusDevice::Unassigned);
for(int c = 0; c < 0x600000; c += 0x100000) {
map_to(c + 0x100000, (c & 0x100000) ? BusDevice::Unassigned : BusDevice::ROM);
}
map_to(0x800000, BusDevice::RAM);
} else {
@ -368,16 +370,16 @@ template <Analyser::Static::Macintosh::Target::Model model> class ConcreteMachin
populate_memory_map([rom_is_overlay] (std::function<void(int target, BusDevice device)> map_to) {
// Addresses up to $80 0000 aren't affected by this bit.
if(rom_is_overlay) {
map_to(0x100000, BusDevice::ROM);
map_to(0x400000, BusDevice::Unassigned);
map_to(0x500000, BusDevice::ROM);
map_to(0x580000, BusDevice::Unassigned);
for(int c = 0; c < 0x580000; c += 0x20000) {
map_to(c + 0x20000, ((c & 0x100000) || (c & 0x20000)) ? BusDevice::Unassigned : BusDevice::ROM);
}
map_to(0x600000, BusDevice::SCSI);
map_to(0x800000, BusDevice::RAM);
} else {
map_to(0x400000, BusDevice::RAM);
map_to(0x500000, BusDevice::ROM);
map_to(0x580000, BusDevice::Unassigned);
for(int c = 0x400000; c < 0x580000; c += 0x20000) {
map_to(c + 0x20000, ((c & 0x100000) || (c & 0x20000)) ? BusDevice::Unassigned : BusDevice::ROM);
}
map_to(0x600000, BusDevice::SCSI);
map_to(0x800000, BusDevice::Unassigned);
}
@ -693,13 +695,13 @@ template <Analyser::Static::Macintosh::Target::Model model> class ConcreteMachin
RAM, ROM, VIA, IWM, SCCWrite, SCCReadResetPhase, SCSI, PhaseRead, Unassigned
};
/// Divides the 24-bit address space up into $80000 (i.e. 512kb) segments, recording
/// Divides the 24-bit address space up into $20000 (i.e. 128kb) segments, recording
/// which device is current mapped in each area. Keeping it in a table is a bit faster
/// than the multi-level address inspection that is otherwise required, as well as
/// simplifying slightly the handling of different models.
///
/// So: index with the top 5 bits of the 24-bit address.
BusDevice memory_map_[32];
/// So: index with the top 7 bits of the 24-bit address.
BusDevice memory_map_[128];
void setup_memory_map() {
// Apply the power-up memory map, i.e. assume that ROM_is_overlay_ = true.
@ -713,8 +715,8 @@ template <Analyser::Static::Macintosh::Target::Model model> class ConcreteMachin
case Model::Mac512ke:
populate_memory_map([] (std::function<void(int target, BusDevice device)> map_to) {
// Up to $60 0000 mirrors of the ROM alternate with unassigned areas every $10 0000 byes.
for(int c = 0; c <= 0x600000; c += 0x100000) {
map_to(c, ((c >> 20)&1) ? BusDevice::ROM : BusDevice::Unassigned);
for(int c = 0; c < 0x600000; c += 0x100000) {
map_to(c + 0x100000, (c & 0x100000) ? BusDevice::Unassigned : BusDevice::ROM);
}
map_to(0x800000, BusDevice::RAM);
map_to(0x900000, BusDevice::Unassigned);
@ -732,10 +734,9 @@ template <Analyser::Static::Macintosh::Target::Model model> class ConcreteMachin
case Model::MacPlus:
populate_memory_map([] (std::function<void(int target, BusDevice device)> map_to) {
map_to(0x100000, BusDevice::ROM);
map_to(0x400000, BusDevice::Unassigned);
map_to(0x500000, BusDevice::ROM);
map_to(0x580000, BusDevice::Unassigned);
for(int c = 0; c < 0x580000; c += 0x20000) {
map_to(c + 0x20000, ((c & 0x100000) || (c & 0x20000)) ? BusDevice::Unassigned : BusDevice::ROM);
}
map_to(0x600000, BusDevice::SCSI);
map_to(0x800000, BusDevice::RAM);
map_to(0x900000, BusDevice::Unassigned);
@ -758,7 +759,7 @@ template <Analyser::Static::Macintosh::Target::Model model> class ConcreteMachin
// to the supplied 24-bit address, setting a particular mapped device.
int segment = 0;
auto map_to = [&segment, this](int address, BusDevice device) {
for(; segment < address >> 19; ++segment) {
for(; segment < address >> 17; ++segment) {
this->memory_map_[segment] = device;
}
};