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asm_S9xSetPCBase:
.file 1 "os9x_asm_cpu.cpp"
.loc 1 16 0
@ args = 0, pretend = 0, frame = 0
@ frame_needed = 0, uses_anonymous_args = 0
MOV R1,R0,LSR #MEMMAP_SHIFT
@ MEMMAP_SHIFT is 12, Address is 0xFFFFFFFF at max, so
@ R1 is maxed by 0x000FFFFF, MEMMAP_MASK is 0x1000-1=0xFFF
@ so AND MEMMAP_MASK is BIC 0xFF000
BIC R1,R1,#0xFF000
bic r0, r0, #0xff0000
@ R2 <= Map[block] (GetAddress)
LDR R2,[reg_cpu_var,#Map_ofs]
LDR R2,[R2,R1,LSL #2]
CMP R2,#MAP_LAST
BLO SPCSpecial @ special
mov regpcbase, r2
add rpc, r2, r0
str rpc, [reg_cpu_var, #PC_ofs]
str regpcbase, [reg_cpu_var, #PCBase_ofs]
bx r3
SPCSpecial:
LDR PC,[PC,R2,LSL #2]
MOV R0,R0 @ nop, for align
.long SPC_PPU
.long SPCDefault
.long SPCDefault
.long SPCDefault
.long SPCDefault
.long SPCDefault
.long SPCDefault
.long SPCDefault
.long SPCDefault
.long SPCDefault
.long SPCDefault
.long SPCDefault
/*
MAP_PPU 0
MAP_CPU 1
MAP_DSP 2
MAP_LOROM_SRAM 3
MAP_HIROM_SRAM 4
MAP_NONE 5
MAP_DEBUG 6
MAP_C4 7
MAP_BWRAM 8
MAP_BWRAM_BITMAP 9
MAP_BWRAM_BITMAP2 10
MAP_SA1RAM 11
MAP_LAST 12
*/
vMemory:
.word Memory
.equ _fillram, 20
SPC_PPU:
@CPU.PCBase = Memory.FillRAM - 0x2000;
@CPU.PC = CPU.PCBase + (Address & 0xffff);
ldr r1, vMemory
ldr r2, [r1, #_fillram]
sub r2, r2, #0x2000
mov regpcbase, r2
add rpc, r2, r0
str rpc, [reg_cpu_var, #PC_ofs]
str regpcbase, [reg_cpu_var, #PCBase_ofs]
@return;
bx r3
@-------------------
SPCDefault:
bx r3
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