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Taichung, Taiwan

How's it going everyone.

Long time, no post.

Currently living in Taipei and got a Gamecube with Gameboy Player. I would like to prosound mod it, but haven't been able to find much in terms of resources. Just need to know where to tap into the board for line level audio.

Any help would be greatly appreciated.

Offline
Sea of Souls

The GB player contains a CPU AGB A, (B is in the SP) so the pinout should be :

Advance Gameboy CPU Pinouts (CPU AGB)
  1 VDD3  17 D0   33 A0    49 WA4   65 VDD2  81 WD9   97 LDB5   113 CK1
  2 IN35  18 A15  34 /CS   50 WA5   66 WD5   82 WD1   98 LDB4   114 CK2
  3 TP8   19 A14  35 /RD   51 WA6   67 WD13  83 /WOE  99 LDB3   115 VDD2
  4 TP0   20 A13  36 /WR   52 WA7   68 WD6   84 DCK   100 LDB2  116 GND
  5 TP1   21 A12  37 PHI   53 /WLB  69 WD14  85 LP    101 LDB1  117 VDD2
  6 SO1   22 A11  38 VDD35 54 /WUB  70 WD7   86 PS    102 GND   118 VCNT5
  7 SO2   23 A10  39 GND   55 /WWE  71 WD15  87 LDR5  103 VDD3  119 TP9
  8 Vin   24 A9   40 SC    56 WA8   72 WD8   88 LDR4  104 SPL   120 TP6
  9 /RES  25 A8   41 SD    57 WA9   73 WD16  89 LDR3  105 CLS   121 TP5
  10 D7   26 A7   42 SI    58 WA10  74 WA16  90 LDR2  106 SPS   122 TP7
  11 D6   27 A6   43 SO    59 WA11  75 WD12  91 LDR1  107 MOD   123 TP4
  12 D5   28 A5   44 VDD2  60 WA12  76 WD4   92 LDG5  108 REVC  124 /FIQ
  13 D4   29 A4   45 WA0   61 WA13  77 WD11  93 LDG4  109 GNDed 125 /RESET
  14 D3   30 A3   46 WA1   62 WA14  78 WD3   94 LDG3  110 GNDed 126 TP2
  15 D2   31 A2   47 WA2   63 WA15  79 WD10  95 LDG2  111 GNDed 127 TP3
  16 D1   32 A1   48 WA3   64 GND   80 WD2   96 LDG1  112 GNDed 128 GND

SO it looks like pins 6 and 7 are what we're looking for...
I'll pull mine apart and get back with you.

...

So probing around, I have found TP30 and TP31 respectively are places to tap into. The board however doesn't have any passive components, so you'll probably need to add a few caps and resistors from these test points.

I'll look at the GBA's schematic for some nintendo-recommended values.

...

ok, looks like the suggested prosound for an original gba is to connect to R30 and R31, which are 47k resistors, but unlike the DMG and pokect there are no coupling caps to worry about. So I guess you can locate a few 47k resistors and solder them to TP30 and TP31 and just connect that to a headphone jack.

...

sources:
https://dragaosemchama.com/wp-content/u … Manual.pdf
https://chipmusic.org/forums/post/250576/#p250576
https://gbhwdb.gekkio.fi/consoles/gbs/

› Show Spoiler

...

It probably wouldn't hurt to slap a massive electrolytic cap on the power rail near the cpu. 1000uF or so.
Positive pin to vcc and negative pin to gnd.
Click me for fake internet points. big_smile
https://www.facebook.com/OfficialOrgiaMode

Last edited by Orgia Mode (Jan 14, 2019 6:57 pm)