6502/CLK
1
0
Fork 0
mirror of https://github.com/TomHarte/CLK.git synced 2024-11-26 08:49:37 +00:00
Code Issues Projects Releases Wiki Activity

Improves memory map model, as far as it goes.

Browse Source
This commit is contained in:
Thomas Harte 2019-04-29 17:27:44 -04:00
parent 8564945713
commit c0e9c37cc7
1 changed files with 4 additions and 6 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

10
OSBindings/Mac/Clock SignalTests/EmuTOSTests.mm
View File

@ -38,17 +38,15 @@ class EmuTOS: public ComparativeBusHandler {
const uint32_t address = cycle.word_address();
uint32_t word_address = address;
if(cycle.address) {
printf("%04x\n", *cycle.address);
}
// As much about the Atari ST's memory map as is relevant here: the ROM begins
// at 0xfc0000, and the first eight bytes are mirrored to the first four memory
// addresses in order for /RESET to work properly. RAM otherwise fills the first
// 512kb of the address space. Trying to write to ROM raises a bus error.
const bool is_peripheral = word_address > (0xff0000 >> 1);
const bool is_rom = word_address > (0xfc0000 >> 1) || word_address < 4;
const bool is_rom = (word_address >= (0xfc0000 >> 1) && word_address < (0xff0000 >> 1)) || word_address < 4;
const bool is_ram = word_address < ram_.size();
const bool is_peripheral = !is_rom && !is_ram;
uint16_t *const base = is_rom ? emuTOS_.data() : ram_.data();
if(is_rom) {
word_address %= emuTOS_.size();