What Are The DOOM SNES Port Music Ranges?

[the_ally235]

I wanted to export the music data from the DOOM SNES port, but I'm not sure where it is exactly, besides probably starting at about 0x70000. I would even more appreciate to know what the ranges are for each specific song (like the specific ranges for e1m1/At Doom' Gate). And yes, I DO have reasons for this.

[DackR]

Perhaps you could compare spc data with data in the rom to determine where the data is stored.

Doom spc files:
http://snesmusic.org/v2/profile.php?profile=set&selected=718

[the_ally235]

Perhaps you could compare spc data with data in the rom to determine where the data is stored.

Doom spc files:
http://snesmusic.org/v2/profile.php?profile=set&selected=718

I want to be sure, but I loaded up one of the SPC files in Notepad++ and I have a part if it where it's skipped over two lines in ASCII view and the part after the two lines skipped over in the ASCII view starts at 0x00000189 in the HEX view, and I was wondering if this is the point where the ROM dump area is located in the SPC file. Image for reference:

EDIT: I think, I think, I got the ranges in the SPC file right for the song's location. Would this be right?
Range in the SPC of E1M1 - 0x00000800 - 0x000016e3
(Please do pardon the long code here)

Spoiler

20 cd ff bd 8f a0 fa 8f a0 fb 8f 20 fc 8f 87 f1 3f 83 10 8f 20 26 8f 1f 27 8f 01 f6 62 08 3f ba 0b 3f 60 0b 33 07 f7 8d 10 3f 4a 07 83 07 12 e4 fe f0 0e e4 cb f0 07 60 84 cc c4 cc 90 03 3f d4 16 e4 fd f0 d9 3f 2d 08 2f d4 e4 ff d0 03 e8 01 6f cb 3d 8f 20 3c cd 14 e4 f6 f0 03 3f ba 0b eb 3d f5 fc 07 c4 f2 f5 28 02 fa f3 3e 64 3e f0 0f b0 09 8b 3e dc d0 f5 ab 3c 2f 04 ab 3e 2f f5 fa 3e f3 1d 10 d3 e4 3c 6f e2 08 2f 02 f2 08 72 08 8d 80 3f ee 0c 3f d1 10 8f 6c f2 8f 3f f3 e3 08 0c cd 20 f5 80 fe af c8 61 90 f8 4f c0 5f 20 07 ff d6 a0 80 6b 50 40 36 28 20 1b 14 10 0e 0b 08 06 05 04 03 02 01 1d 1c 1b 1a 19 18 17 16 15 14 13 12 11 10 0f 0e 0d 0c 0a 09 06 20 08 18 28 38 48 58 68 78 07 17 27 37 47 57 67 77 04 14 24 34 44 54 64 74 02 12 22 32 42 52 62 72 20 10 20 30 40 50 60 70 01 11 21 31 41 51 61 71 2c 3c 0d 0c 1c 01 02 04 08 10 20 40 80 fe fd fb f7 ef df bf 7f 7d 2c 3c 0d 0f 1f 2f 3f 4f 5f 6f 7f 3f ba 0b 8f 20 47 8f 20 59 8f 7c f2 e4 f3 24 5c c4 56 8f 20 f3 cd 07 3f ba 0b d8 2a 7d 60 88 10 c4 2f f5 11 08 c4 48 48 ff c4 49 f4 65 c4 4b a2 08 23 4b 06 f5 ec fc 5f 75 08 eb 2f f6 e3 04 d0 02 b2 08 3f 60 12 f8 2a 75 f4 fc d0 0d 3f 1e 14 e4 61 24 5a 24 48 d0 43 2f 44 d5 f4 fc 09 48 47 3f 1e 14 7d 1c 5d e5 04 01 d5 4b 01 e5 05 01 d5 4c 01 f8 2a e4 62 28 20 f0 05 29 49 57 2f 03 09 48 57 b3 08 0b e4 62 28 40 f0 05 09 48 61 2f 03 29 49 61 e4 61 04 5a 24 48 f0 03 09 48 59 1d 30 03 5f 44 08 e4 5a 24 57 04 58 c4 58 24 58 04 59 c4 5b 8f 5c f2 c4 f3 cd 07 3f ba 0b d8 2a f5 11 08 c4 48 7d 60 88 18 c4 2f e5 a2 03 d0 12 f4 65 c4 4b 63 4b 06 f5 e4 fc 5f 0d 09 3f 60 12 f8 2a 60 95 9a 03 30 06 70 04 68 65 30 0b f5 9a 03 30 04 e8 64 2f 02 e8 20 fd f5 43 01 c4 3e cf cd 64 9e f8 2a 73 4b 14 c4 3c 6d eb 2f f6 c3 03 ee d0 04 e4 3c 2f 05 e4 3e 80 a4 3c c4 3c d5 28 02 e4 3e 80 a4 3c d5 30 02 1d 30 03 5f e6 08 cd 07 3f ba 0b d8 2a 7d 60 88 08 c4 2f f4 65 c4 4b 7d 1c 5d f5 d5 fc c4 46 f5 d4 fc c4 45 53 4b 15 4d 42 08 3f 60 12 52 08 ce 7a 45 80 a8 b0 c4 45 dd a8 04 c4 46 f5 4c 01 fd f5 4b 01 7a 45 da 3c fb d9 f4 d8 7a 3c c3 4b 03 3f a0 14 da 3c e4 2a 1c 5d f5 5c 01 fd f5 5b 01 7a 3c f8 2a d5 33 01 dd d5 3b 01 1d 10 9a 8f 5c f2 8f 20 f3 cd 07 3f ba 0b d8 2a 7d 60 88 20 c4 2f f5 11 08 c4 48 48 ff c4 49 f4 65 c4 4b 03 4b 07 f5 23 01 fd 5f f9 09 3f 60 12 fd f8 2a b3 07 04 e8 20 d4 6d e8 80 de 6d 04 e4 5e 2f 02 e4 5d cf f5 92 03 cf dd d5 2b 01 8f c0 3b f5 dc 07 c4 f2 dd 80 a4 f3 b0 06 8f 80 3b 48 ff bc c4 40 e4 48 24 55 d0 06 e4 54 24 48 d0 23 e4 40 5c d0 08 ad 20 d0 04 e8 82 2f 0e 8d 15 76 b0 07 90 02 fe f9 f6 c6 07 04 3b 75 cc fc f0 41 fd 2f 17 8f 20 3b e4 40 68 60 90 0e ad 60 90 04 8d df 2f 06 ad 20 b0 02 8d 9e 29 49 54 f5 fc 07 c4 f2 f5 28 02 2d e4 48 24 55 ae d0 09 c4 f3 ab f2 f5 30 02 c4 f3 f5 e4 07 c4 f2 cb f3 dd d5 cc fc f5 f4 07 c4 f2 fd f5 33 01 c4 f3 fc cb f2 f5 3b 01 c4 f3 1d 30 03 5f ca 09 8f 4c f2 fa 5b f3 e4 5b 48 ff c4 5c 29 5c 56 29 5c 58 8f 20 5a 3f ba 0b 8d 07 cd 0e 3f ba 0b f6 6d 20 f0 31 f6 65 20 c4 4b f3 4b 07 f6 11 08 24 56 d0 1d f6 6d 20 68 80 d0 1b f6 46 02 28 02 d0 14 9b 76 f4 76 2e 05 02 9b 77 f4 76 14 77 d0 05 e8 80 3f ff 16 1d 1d dc 10 c2 3f ba 0b ec 43 02 f0 54 6e cd 51 cb cd e5 3b 02 f8 ce 30 0d 60 84 cf b0 04 68 7f 90 12 e8 7f 2f 09 80 a4 cf f0 04 b0 07 e8 20 8d 20 cc 43 02 5d 65 44 02 90 03 e5 44 02 c5 38 02 7d c5 3b 02 c5 3c 02 65 45 02 90 03 e5 45 02 c5 39 02 e5 43 02 d0 0a aa 07 40 90 05 8d 80 5f ee 0c 6f 32 08 e4 e8 f0 2f 9c c4 e8 f8 ea f5 23 10 28 fe c4 32 f5 43 10 c4 33 f5 63 10 c4 34 3d c8 20 d0 02 cd 20 d8 ea e4 32 5d 28 fe c8 4d b0 07 e4 33 eb 34 3f 96 0b 6f 1f 0d 1e 6d 4d ba f4 da 1a f8 f6 8f b7 f1 8d 20 f7 1a c4 f4 fc f7 1a c4 f5 fc f7 1a c4 f7 d8 f6 ce ee ae 6f 73 08 28 69 03 f6 f0 23 69 eb f6 f0 1e 2d e4 f6 f0 18 2e f6 15 e4 f7 68 22 f0 6d 23 08 0c fa f6 eb 2f 09 e4 f6 8f b7 f1 c4 f6 ae 6f 68 0c f0 af 68 48 d0 03 5f 88 07 68 0e d0 03 5f 8c 07 68 02 d0 15 4d 6d e4 f6 8f b7 f1 2d 72 08 3f 7e 0c 62 08 ae c4 f6 ee 2f 2b 4d f8 e9 d5 23 10 e4 f4 d5 43 10 e4 f5 d5 63 10 e4 f6 8f b7 f1 c4 f6 3d c8 20 d0 02 cd 20 d8 e9 e4 e8 bc c4 e8 68 20 d0 02 22 08 ce ae 5f ba 0b 6f 6d 4d fa f6 eb ba f4 da 1a f8 f6 d8 f6 ad 20 f0 1d 8d 20 3e f6 f0 fc e4 f4 d7 1a e4 f5 fc d7 1a e4 f7 f8 f6 30 df d8 f6 fc d7 1a fc 2f e5 e4 f6 8f b7 f1 c4 f6 ce ee ae 5f ba 0b 6f 3f f6 10 3f ec 10 22 07 6f c5 a2 03 6f e8 20 c5 43 02 6f cd 01 52 07 2f 02 cd ff c5 43 02 c4 cd cb cf d8 ce 6f 2d dd 28 7f c5 3e 02 ae 92 08 2f 05 cc 40 02 82 08 5f 4a 0d 3f 90 1c e5 fc 1e c5 8b 06 e5 fd 1e c5 8c 06 05 8b 06 f0 20 3f d4 16 e5 8b 06 80 a8 01 c5 8b 06 e5 8c 06 a8 20 c5 8c 06 b0 ea cd 07 e8 20 d5 43 01 1d 10 fa 6f 8d ff cd 07 ad 80 f0 04 ad ff d0 08 82 07 8f 20 87 8f ff 0c c4 75 ad 80 f0 1b f4 d0 68 ff f0 30 68 20 10 06 ad ff f0 0d 2f 26 ad 20 d0 07 f5 1b 01 64 75 d0 1b f5 e4 07 c4 f2 8f 9f f3 f5 ec 07 e8 20 d5 23 01 d4 6d d4 65 f5 11 08 04 5a c4 5a 1d 10 c3 6f 52 07 5f 97 0c 42 07 5f 97 0c 8d 0e c4 75 3f ff 0f da 24 8d 20 f7 24 c4 50 3a 24 8d 07 f7 24 24 0c c4 51 8d 06 f7 24 c4 52 8f 80 53 cd 07 3f 25 0e 10 03 5f f7 0d 83 08 07 e8 02 15 46 02 2f 05 e8 fd 35 46 02 d5 46 02 e8 80 d4 6d e5 3e 02 d4 d0 e5 3f 02 d5 92 03 e5 40 02 d5 9a 03 e5 8e 03 c4 0f e5 90 03 c4 0e e5 8f 03 c4 10 e5 91 03 c4 11 7d 1c fd e8 20 d6 5b 01 d6 5c 01 c5 3d 02 e5 41 02 d6 d8 20 e5 42 02 d6 d9 20 e4 75 d5 1b 01 8d 02 f7 24 c4 4c fc f7 24 c4 4d 8d 04 f7 24 c4 4e fc f7 24 c4 4f 8d 01 f7 24 2d 8d 20 f7 24 02 07 ee 72 07 3f a0 0e 60 98 08 24 90 02 ab 25 8b 50 f0 03 5f 5b 0d e8 20 c5 3e 02 c5 41 02 c5 42 02 c5 40 02 c5 8e 03 c5 90 03 c5 8f 03 c5 91 03 9c c5 3f 02 6f 8f 01 0b 03 09 03 8f 20 0b 83 0b 5a 8d 07 8f ff 3c 8f ff 3d 73 0b 08 c8 08 b0 4b 8d 20 2f 09 3f ba 0b e4 53 24 51 f0 1f f4 6d f0 41 e4 52 03 0b 06 74 12 b0 38 2f 10 74 12 f0 0c 90 0a f4 12 64 3d b0 04 c4 3d d8 3c 53 0b 0c 0b 53 d0 05 8f 01 53 cd ff 3d 2f 0a 4b 53 d0 05 8f 80 53 cd 08 1d dc 10 bc 03 0b 03 e8 ff 6f f8 3c 30 f9 33 0b 04 f4 6d d0 f2 e4 52 d4 12 e8 20 6f d8 2a d8 4a 2d f5 46 02 28 fe d5 46 02 63 07 08 f5 e4 07 c4 f2 8f 9f f3 dd d5 43 01 7d 1c 5d e4 4e d5 d4 fc e4 4f d5 d5 fc e4 4c d4 76 e4 4d d4 77 ae 8d 02 3f ff 0f da 22 f8 4a f5 11 08 c4 63 48 ff c4 64 e4 55 63 07 05 35 19 08 2f 03 15 11 08 c4 55 8d 20 f7 22 d4 65 c4 4b 8f 2d f2 28 20 f0 05 09 63 f3 2f 03 29 64 f3 63 07 50 b0 4e 93 4b 45 13 08 05 e5 06 01 2f 04 8d 05 f7 22 8d 0c 3f ff 0f 8d 20 f6 21 08 c4 f2 f7 2b ad 01 f0 08 ad 03 f0 0f ad 02 d0 10 d6 43 02 65 3b 02 90 03 e5 3b 02 d6 37 02 2f 02 c4 f3 fc ad 0c 90 d6 8f 4d f2 09 63 f3 2f 06 8f 4d f2 29 64 f3 e4 4a 60 88 20 c4 2f 8d 01 f7 22 03 4b 08 f8 4a d5 23 01 5f 7e 0f 8d 04 3f ff 0f fa 0f 0d 3f 90 11 e4 4a 60 88 08 c4 2f 53 4b 13 8d 03 f7 22 8d 06 3f ff 0f fa 10 0d 42 08 3f 90 11 52 08 e4 4a 60 88 18 c4 2f 63 07 57 8d 04 f7 22 63 4b 08 f8 4a d5 e4 fc 5f d5 0f 8d 08 3f ff 0f fa 11 0d 3f 90 11 eb 2f f6 e3 04 f0 0a f6 c3 03 d0 05 e8 ff 5f d2 0f e8 20 d6 c3 03 e4 4a 60 88 10 c4 2f 8d 02 f7 22 23 4b 08 f8 4a d5 ec fc 5f f6 0f 8d 0a 3f ff 0f fa 0e 0d 3f 90 11 09 63 5a 09 63 54 72 07 6f 3f ba 0b 8f 20 21 1c 2b 21 60 96 e0 1e c4 20 e4 21 96 e1 1e c4 21 8d 01 f7 20 c4 2c dc f7 20 c4 2b eb 2c 6f 24 4a 06 12 1a 1c 24 65 6f 50 61 6e 2b 58 2c 41 0d 0a 20 20 20 20 20 20 20 20 20 20 20 64 65 63 01 01 02 01 20 80 01 20 20 20 20 20 20 20 20 6d 6f 76 20 50 6c 61 79 43 68 61 6e 2b 58 2c 41 0d 7f 20 04 10 20 80 7f 20 20 20 20 20 6d 6f 76 20 50 6c 61 79 43 75 72 56 65 6c 6f 63 69 74 79 2b 3f d1 10 cd 35 8d 11 3f 1e 11 e8 20 5d fd d5 20 01 af c8 f0 90 f8 5d d5 20 02 d5 20 03 d5 20 04 d5 20 05 d5 20 06 d5 20 fc d5 20 fd d5 20 ff 3d d0 e5 e8 ff c4 56 c4 58 c4 61 c4 57 c4 5c c4 5d c4 5e c5 3f 02 c4 05 c4 06 c4 0c 82 07 6f cd 14 e8 20 d5 28 02 1d 10 fa 8f 10 3c 8d 10 3f 4a 07 68 20 f0 04 8b 3c d0 f0 6f e8 7f c5 3b 02 c5 3c 02 2f e5 e5 e1 1e 8f 6d f2 c4 f3 68 ff f0 1b c4 01 e8 20 fd c4 20 d7 20 fe fc ab 01 78 fc 01 d0 f5 8f 6c f2 e8 df 24 f3 c4 f3 6f d8 20 cb 01 8d 20 f7 20 68 ff f0 0a c4 f2 fc f7 20 c4 f3 fc d0 f0 6f 3d 20 4d 20 0d 20 7d 20 0f 20 1f 20 2f 20 3f 20 4f 20 5f 20 6f 20 7f 20 6d ff 2c 20 3c 20 0c 20 1c 20 5d 02 5c 20 2d 20 04 08 14 08 24 08 34 08 44 08 54 08 64 08 74 08 07 20 17 20 27 20 37 20 47 20 57 20 67 20 77 20 05 20 15 20 25 20 35 20 45 20 55 20 65 20 75 20 7c 20 ff 3f ba 0b f8 2f 8d 07 f7 2b d5 e3 04 dc dc f7 2b d5 03 04 dc f7 2b d5 c3 04 dc f7 2b d5 23 04 dc f7 2b d5 43 04 dc f7 2b d5 83 04 dc f7 2b d5 63 04 eb 2f e4 2b 60 88 08 d6 43 05 e4 2c 88 20 d6 63 05 f6 23 04 cd 20 eb 0d f0 23 cf cb 3c c4 3d cd 05 4b 3c 7c 1d d0 fa eb 3c ad 20 d0 08 68 20 f0 0a f8 3d 2f 08 cd 01 e8 ff 2f 02 5d bc eb 2f d6 23 04 7d 48 ff 08 e0 d6 a3 03 e8 ff d6 e3 03 3f ba 0b 5d f6 43 04 fd 7d cf da 43 03 07 06 ba 05 da 43 2f 0a ba 4c 9a 43 b0 02 ba 4c cb 44 eb 2f d6 83 05 e4 44 d6 a3 05 f6 23 04 bc d0 01 9c d6 03 05 68 03 b0 05 e8 20 d6 c3 04 e8 01 d6 a3 04 9c d6 23 05 d6 44 ff d6 64 ff c4 39 5f 32 13 eb 2f b2 07 f6 c3 04 c4 39 f6 a3 04 f0 42 f6 a3 03 60 96 e3 03 d6 e3 03 90 18 f6 03 05 c4 3a f0 03 9c d0 03 f6 23 04 d6 03 05 78 02 3a 90 08 5f 32 13 8f 20 39 2f f8 eb 2f f6 23 05 bc 76 03 04 90 1b 9c 76 83 04 d0 03 5f 2c 13 e8 20 d6 a3 04 a2 07 f6 24 ff 2d f6 04 ff ee 5f e3 13 d6 23 05 f6 a3 05 16 83 05 f0 6a f8 2a f5 46 02 28 02 f0 24 e8 01 74 6d d0 03 83 07 09 eb 2a f6 46 02 28 01 f0 3d e8 20 d6 76 20 d6 77 20 eb 2f d6 83 05 d6 a3 05 2f 21 f6 83 05 80 b6 23 04 d6 83 05 c4 43 f6 a3 05 a8 20 b0 07 e8 20 d6 83 05 c4 43 d6 a3 05 04 43 d0 0a f6 83 04 76 03 04 90 11 a2 07 eb 2f f6 23 05 76 83 04 90 08 f0 06 f6 63 04 d6 23 05 eb 2f f8 39 f0 1c 78 03 3a 90 17 f6 04 ff c4 35 f6 24 ff c4 36 f6 44 ff c4 37 f6 64 ff c4 38 5f d1 13 f6 43 05 c4 2d f6 63 05 c4 2e f6 23 05 fd 43 08 07 f7 2d 8d 40 cf 2f 10 8d 02 cf 7a 2d da 2d 8d 01 f7 2d dc 2d f7 2d ee f8 39 f0 55 78 02 3a f0 50 da 3c eb 2f f6 24 ff c4 36 f6 04 ff c4 35 eb 36 80 9a 3c da 37 e8 20 3c c4 3c d0 08 58 ff 37 58 ff 38 3a 37 eb 2f f6 23 04 5d ba 37 3f ee 13 c4 37 d8 38 78 01 3c d0 08 58 ff 37 58 ff 38 3a 37 eb 2f e4 37 d6 44 ff e4 38 d6 64 ff ba 35 7a 37 da 35 eb 2f d6 04 ff e4 36 d6 24 ff ba 35 43 08 07 cd 40 9e 8d 20 da 35 6f c8 20 d0 04 1d 7d fd 6f 40 cb 01 3e 01 f0 02 b0 1a c4 20 dd 8d 20 9e c4 02 fd 7d cf c4 03 e4 01 80 a4 03 fd e4 20 9e f8 02 20 6f 9e cd 20 20 6f 4d f5 f4 fc 8d 04 cf 7a 26 da 20 f5 ec 07 c4 f2 7d 1c 1c 5d f5 02 02 c5 26 02 f5 03 02 c5 27 02 8f 09 f3 8d 20 f7 20 d5 20 02 fc f7 20 d5 01 02 fc f7 20 d5 02 02 fc f7 20 d5 03 02 8d 01 f7 20 c4 3f dc f7 20 80 a8 03 c4 3e b8 20 3f f7 3e c5 04 01 fc f7 3e c5 05 01 fc f7 3e c4 62 10 14 28 1f 8f 6c f2 38 e0 f3 04 f3 c4 f3 8f 3d f2 09 48 f3 2f 06 8f 3d f2 29 49 f3 ce f5 ec 07 c4 f2 d8 f3 6f 60 88 a0 5d dd 88 05 fd 7d ad 0a 90 06 d0 0a 68 50 b0 06 8f ff 42 5f cf 14 ad 80 90 0f 8f 20 42 60 88 20 5d dd 88 df fd 7d 5f cf 14 8f 0a 42 cd f0 9e 78 ff 42 d0 02 c4 42 f6 f4 14 c4 3c f6 e4 15 c4 3d e8 0a 80 a4 42 f0 07 fd 4b 3d 6b 3c fe fa ba 3c 6f 20 18 2f 47 5f 77 8f a7 bf d8 f0 08 21 39 52 6b 83 9c b5 ce e7 20 19 33 4c 65 7f 98 b2 cc e5 ff 19 33 4d 67 82 9c b6 d1 eb 06 20 3b 56 71 8c a7 c2 dd f9 14 2f 4b 67 82 9e ba d6 f2 0e 2a 46 63 7f 9c b8 d5 f2 0f 2b 48 66 83 a0 bd db f8 16 34 51 6f 8d ab c9 e7 06 24 43 61 80 9e bd dc fb 1a 39 59 78 97 b7 d7 f6 16 36 56 76 96 b7 d7 f7 18 39 59 7a 9b bc dd ff 20 41 63 84 a6 c8 ea 0c 2e 50 72 95 b7 da fc 1f 42 65 88 ab cf f2 16 39 5d 81 a5 c9 ed 11 35 5a 7e a3 c8 ed 12 37 5c 81 a6 cc f2 17 3d 63 89 af d6 fc 22 49 70 97 be e5 0c 33 5a 82 aa d1 f9 21 49 71 9a c2 eb 13 3c 65 8e b7 e0 0a 33 5d 87 b0 da 04 2f 59 84 ae d9 04 2f 5a 85 b0 dc 07 33 5f 8b b7 e3 0f 3c 68 95 c2 ef 1c 49 77 a4 d2 20 2e 5c 8a b8 e7 15 44 73 a2 d1 

[close]

[DackR]

Yes, that's definitely where the actual song data starts. I'm not sure where it ends, however.

In the ROM, the code for the sound driver starts around $ED60B-ish, and I'm fairly certain the actual data being sent to the SPC700 is directly above that. It looks like the spc data in the ROM is compressed (could be wrong).

I can't help much more than that currently, but if you run a trace while the game boots up, it will load the data for the first two songs into APU RAM.

Just check for writes to register $2141 and check above that in the code to see where the data is coming from. Typically, you should see it transfer the music data from a ROM (ex. ~$4ed5e4) address into a RAM (ex. ~$7f75aa) address-- especially if it's decompressing data-- before storing it in APU RAM. You'll want to convert all addresses referenced in the disassembled code from HIROM addressing to PC addressing (the ROM address I just mentioned would convert to ($ED5E4 PC). Just from quickly looking at the code, this should be where your search should start.

Hopefully that will get you started. Others may wish to chime in that have more experience with the APU. Feel free to correct me if any of my assumptions are wrong as well.

Unfortunately, this is about as much as I know about how the APU functions as I've not had to deal with it much before. Good luck, my friend.