Cb read

00020840: 27bdffd0 addiu r29,r29,0xffd0
00020844: afb10024 sw r17,0x0024(r29)
00020848: 00a08821 addu r17,r5,r0                 # p2
0002084c: 308400ff andi r4,r4,0x00ff
00020850: 34020001 ori r2,r0,0x0001
00020854: afbf0028 sw r31,0x0028(r29)
00020858: 1482003a bne r4,r2,0x00020944           # 
0002085c: afb00020 sw r16,0x0020(r29)
00020860: 3c108003 lui r16,0x8003
00020864: 26101ba0 addiu r16,r16,0x1ba0           # number of sections to load
00020868: 8e020000 lw r2,0x0000(r16)
0002086c: 00000000 nop
00020870: 18400038 blez r2,0x00020954             # branch if erroneous
00020874: 00000000 nop
00020878: 3c038003 lui r3,0x8003
0002087c: 8c631b9c lw r3,0x1b9c(r3)               # num bytes per sector
00020880: 34020200 ori r2,r0,0x0200
00020884: 14620010 bne r3,r2,0x000208c8           # branch if not 2048 bytes per sector
00020888: 27a40010 addiu r4,r29,0x0010

fft's sectors are all 2328 bytes? so this code will never run. probably.

0002088c: 0c007bd5 jal 0x0001ef54                 # S 021 CDGetSector filesize = 3 store file's metadata (format CdIFILE) to stack
00020890: 34050003 ori r5,r0,0x0003
00020894: 0c007c30 jal 0x0001f0c0                 # SYS CDPosToInt <- get LBA of file
00020898: 27a40010 addiu r4,r29,0x0010            # parse location of file header?
0002089c: 3c038003 lui r3,0x8003
000208a0: 8c631bac lw r3,0x1bac(r3)
000208a4: 00000000 nop
000208a8: 10430007 beq r2,r3,0x000208c8           # branch if it matches file to load's LBA file (ideally, always)
000208ac: 00000000 nop
000208b0: 3c048001 lui r4,0x8001
000208b4: 24840420 addiu r4,r4,0x0420
000208b8: 0c0088a3 jal 0x0002228c                 # Write String to Terminal "CdRead: sector error\n"
000208bc: 00000000 nop
000208c0: 2402ffff addiu r2,r0,0xffff
000208c4: ae020000 sw r2,0x0000(r16)              # store cd Read failstate = -1
000208c8: 3c108003 lui r16,0x8003
000208cc: 26101b94 addiu r16,r16,0x1b94
000208d0: 8e040000 lw r4,0x0000(r16)              # ram address to load file into
000208d4: 3c058003 lui r5,0x8003
000208d8: 8ca51b9c lw r5,0x1b9c(r5)               # load sector size >> 2
000208dc: 0c007bd5 jal 0x0001ef54                 # S 021 CDGetSector
000208e0: 00000000 nop
000208e4: 3c028003 lui r2,0x8003
000208e8: 8c421b9c lw r2,0x1b9c(r2)
000208ec: 8e030000 lw r3,0x0000(r16)              # Ram address to load into
000208f0: 00021080 sll r2,r2,0x02                 # sector size
000208f4: 00431021 addu r2,r2,r3                  # sector size + ram address to load into (word of last address of file)
000208f8: ae020000 sw r2,0x0000(r16)              # re-store
000208fc: 3c028003 lui r2,0x8003
00020900: 8c421ba0 lw r2,0x1ba0(r2)               # number of sections of file to load
00020904: 00000000 nop
00020908: 2442ffff addiu r2,r2,0xffff
0002090c: 3c018003 lui r1,0x8003
00020910: ac221ba0 sw r2,0x1ba0(r1)               # restore
00020914: 3c028003 lui r2,0x8003
00020918: 8c421ba0 lw r2,0x1ba0(r2)               # this does nothing
0002091c: 3c028003 lui r2,0x8003
00020920: 8c421bac lw r2,0x1bac(r2)               # LBA of file to load
00020924: 00000000 nop
00020928: 24420001 addiu r2,r2,0x0001             # add 1 (oh interesting... so, this is called multiple times for large files then?)
0002092c: 3c018003 lui r1,0x8003
00020930: ac221bac sw r2,0x1bac(r1)
00020934: 3c028003 lui r2,0x8003
00020938: 8c421bac lw r2,0x1bac(r2)
0002093c: 08008255 j 0x00020954
00020940: 00000000 nop

if p1 = 1;

00020944: 3c038003 lui r3,0x8003
00020948: 24631ba0 addiu r3,r3,0x1ba0 
0002094c: 2402ffff addiu r2,r0,0xffff             # -1
00020950: ac620000 sw r2,0x0000(r3)               # skip moving a sector

00020954: 0c0076ea jal 0x0001dba8                 # Vsync
00020958: 2404ffff addiu r4,r0,0xffff
0002095c: 3c038003 lui r3,0x8003
00020960: 24631ba4 addiu r3,r3,0x1ba4
00020964: ac620000 sw r2,0x0000(r3)               # store frame counter since game open
00020968: 3c028003 lui r2,0x8003
0002096c: 8c421ba0 lw r2,0x1ba0(r2)               # number of sections of file to load
00020970: 00000000 nop
00020974: 04410003 bgez r2,0x00020984             # loop for all sections of file to load!
00020978: 00000000 nop
0002097c: 0c008299 jal 0x00020a64                 # cd_read_retry
00020980: 34040001 ori r4,r0,0x0001               # 1 (disables doing certain things?)
00020984: 0c0076ea jal 0x0001dba8                 # Vsync
00020988: 2404ffff addiu r4,r0,0xffff
0002098c: 3c038003 lui r3,0x8003
00020990: 8c631ba8 lw r3,0x1ba8(r3)               # another reference to absolute time after boot
00020994: 00000000 nop
00020998: 246304b0 addiu r3,r3,0x04b0             # + 0x4b0
0002099c: 0062182a slt r3,r3,r2
000209a0: 10600003 beq r3,r0,0x000209b0           # branch if vsync came back early?
000209a4: 2402ffff addiu r2,r0,0xffff
000209a8: 3c018003 lui r1,0x8003
000209ac: ac221ba0 sw r2,0x1ba0(r1)               # set number of file sections to load = -1 (fail state)
000209b0: 3c028003 lui r2,0x8003
000209b4: 8c421ba0 lw r2,0x1ba0(r2)
000209b8: 00000000 nop
000209bc: 1040000a beq r2,r0,0x000209e8           # branch if 0 file sections to load
000209c0: 00000000 nop
000209c4: 0c0076ea jal 0x0001dba8                 # Vsync
000209c8: 2404ffff addiu r4,r0,0xffff
000209cc: 3c038003 lui r3,0x8003
000209d0: 8c631ba8 lw r3,0x1ba8(r3)
000209d4: 00000000 nop
000209d8: 246304b0 addiu r3,r3,0x04b0
000209dc: 0062182a slt r3,r3,r2
000209e0: 1060001a beq r3,r0,0x00020a4c           # end if vsync came back early?
000209e4: 00000000 nop
000209e8: 3c048003 lui r4,0x8003
000209ec: 8c841bb0 lw r4,0x1bb0(r4)               # 
000209f0: 0c007ad6 jal 0x0001eb58                 # CdSyncCallback define cd sync callback for after CDlPause
000209f4: 00000000 nop
000209f8: 3c048003 lui r4,0x8003
000209fc: 8c841bb4 lw r4,0x1bb4(r4)               # 
00020a00: 0c007adc jal 0x0001eb70                 # CdReadyCallback define cd ready callback from variables set elsewhere
00020a04: 00000000 nop
00020a08: 34040009 ori r4,r0,0x0009
00020a0c: 00002821 addu r5,r0,r0
00020a10: 0c007ae2 jal 0x0001eb88                 # CdControl CDlPause
00020a14: 00003021 addu r6,r0,r0
00020a18: 3c038003 lui r3,0x8003
00020a1c: 8c631b88 lw r3,0x1b88(r3)               # get CDReadCallback func
00020a20: 00000000 nop
00020a24: 10600009 beq r3,r0,0x00020a4c           # skip if NULL
00020a28: 00000000 nop
00020a2c: 3c028003 lui r2,0x8003
00020a30: 8c421ba0 lw r2,0x1ba0(r2)               # num file sections to load
00020a34: 00000000 nop
00020a38: 14400002 bne r2,r0,0x00020a44           # if not 0, parse 5
00020a3c: 34040005 ori r4,r0,0x0005 
00020a40: 34040002 ori r4,r0,0x0002               # else parse 2
00020a44: 0060f809 jalr r3,r31                    # do routine as defined by last CDReadCallback
00020a48: 02202821 addu r5,r17,r0                 # p2
00020a4c: 8fbf0028 lw r31,0x0028(r29)
00020a50: 8fb10024 lw r17,0x0024(r29)
00020a54: 8fb00020 lw r16,0x0020(r29)
00020a58: 27bd0030 addiu r29,r29,0x0030
00020a5c: 03e00008 jr r31
00020a60: 00000000 nop