Load Nibble of Compressed Graphic Data
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0007a9b0: 3c028009 lui r2,0x8009 0007a9b4: 8c4262c8 lw r2,0x62c8(r2) #load upper/lower nibble from graphics data 0007a9b8: 00000000 nop 0007a9bc: 1440000a bne r2,r0,0x0007a9e8 #branch if loading lower nibble from graphics data 0007a9c0: 00000000 nop 0007a9c4: 3c028009 lui r2,0x8009 0007a9c8: 8c4262d0 lw r2,0x62d0(r2) 0007a9cc: 3c038009 lui r3,0x8009 0007a9d0: 8c6362cc lw r3,0x62cc(r3) #obtain pointer to current graphics data to decompress 0007a9d4: 00000000 nop 0007a9d8: 00431021 addu r2,r2,r3 0007a9dc: 90420000 lbu r2,0x0000(r2) 0007a9e0: 0801ea85 j 0x0007aa14 0007a9e4: 00021902 srl r3,r2,0x04 #return upper nibble of graphics byte 0007a9e8: 3c028009 lui r2,0x8009 0007a9ec: 8c4262d0 lw r2,0x62d0(r2) #pointer to global graphics data? 0007a9f0: 3c038009 lui r3,0x8009 0007a9f4: 8c6362cc lw r3,0x62cc(r3) #current position in graphics data 0007a9f8: 00000000 nop 0007a9fc: 00431021 addu r2,r2,r3 0007aa00: 90420000 lbu r2,0x0000(r2) #load byte at location 0007aa04: 24630001 addiu r3,r3,0x0001 #increment pointer addition? 0007aa08: 3c018009 lui r1,0x8009 0007aa0c: ac2362cc sw r3,0x62cc(r1) #store incremented current pos. 0007aa10: 3043000f andi r3,r2,0x000f #obtain nibble 0007aa14: 3c028009 lui r2,0x8009 0007aa18: 8c4262c8 lw r2,0x62c8(r2) # 0007aa1c: 00000000 nop 0007aa20: 38420001 xori r2,r2,0x0001 #flip nibble bit 0007aa24: 3c018009 lui r1,0x8009 0007aa28: ac2262c8 sw r2,0x62c8(r1) #store again 0007aa2c: 03e00008 jr r31 0007aa30: 00601021 addu r2,r3,r0 #return graphics data to interpret
