
         ⪮ ᠭ General Instruments / AY-3-8910 (12)
         --------------------------------------------------------

: Yamaha 2149F ( ਣ AY  稯  Yamaha 
ࠧ     㭪).

Vss 1 +----+ 40 Vcc
 NC 2 !    ! 39 TEST1
ACHB 3 !    ! 38 ACHC
ACHA 4 !    ! 37 DA0
 NC 5 !    ! 36 DA1
IOB7 6 !    ! 35 DA2
IOB6 7 !    ! 34 DA3
IOB5 8 !    ! 33 DA4
IOB4 9 !    ! 32 DA5
IOB3 10 !    ! 31 DA6
IOB2 11 !    ! 30 DA7
IOB1 12 !    ! 29 BC1
IOB0 13 !    ! 28 BC2
IOA7 14 !    ! 27 BDIR
IOA6 15 !    ! 26 TEST2
IOA5 16 !    ! 25 A8
IOA4 17 !    ! 24 A9*
IOA3 18 !    ! 23 RESET*
IOA2 19 !    ! 22 CLOCK
IOA1 20 +----+ 21 IOA0

Vcc + 5 V

r# name  used by    description
===============================================================================
00 R0  Tone Gen.   Channel A Fine Tune Register          8   A
01 R1  Tone Gen.   Channel A Coarse Tune Register       孨 4   A
02 R2  Tone Gen.   Channel B Fine Tune Register          8   B
03 R3  Tone Gen.   Channel B Coarse Tune Register       孨 4   B
04 R4  Tone Gen.   Channel C Fine Tune Register          8   C
05 R5  Tone Gen.   Channel C Coarse Tune Register       孨 8   C
06 R6  Noise Gen.  Noise Period Register                 㬠 (㤠୨)
07 R7  Mixer,I/O   Mixer Control - I/O Enable Register   (xxCBA CBA)
08 R10 Amp.Control Channel A Amplitude Control Register ஬  A
09 R11 Amp.Control Channel B Amplitude Control Register ஬  B
0A R12 Amp.Control Channel C Amplitude Control Register ஬  C
0B R13 Envelope Gn Envelope Fine Tune Register           8  .
0C R14 Envelope Gn Envelope Coarse Tune Register        孨 4  ..
0D R15 Envelope Gn Envelope Shape/Cycle Ctrl Register   ଠ 饩
0E R16 I/O         I/O Port A Data Store                ???
0F R17 I/O         I/O Port B Data Store                ???
================================================================================

 16 ॣ஢   1 .  ᯮ짮 AY    뢠
ᯥ䨪 ᯮᮡ 祭  ࠡ  .ᮯ஬ । RDC:
    (177714o)    AY-ॣ (0-15), 
  - . ஬ ⮣,    177714  .
  ⮡  0 ॣ  뤠 :

MOV #377, @#177714 (376 - , 375 - ன   ).

  ᠬ ⭮  .  .

-------------------------------------------------------------------------------

ଠ ॣ஢ 00, 02, 04 ( 8   ᪮ ):

bit#  7 6 5 4 3 2 1 0
      L L L L L L L L

 7-0   8     ᮮ⢥饬 
         (00 -  A, 02 -  B, 04 -  C).   ᫮ ⥬
           㪠 ()   - 襥 ᫮ ᮮ⢥
          ᮪ . 孨 4  室  ॣ 01, 03, 05
         ᮮ⢥⢥ (  A, B, C).
-------------------------------------------------------------------------------

ଠ ॣ஢ 01, 03, 05 (孨 4   ᪮ ):

bit#  7 6 5 4 3 2 1 0
      x x x x H H H H

 3-0  孨 4        묨  ॣ஢
         00, 02  04  १ 12 - ⮢  
         (HHHH LLLL LLLL).
-------------------------------------------------------------------------------

ଠ ॣ 06 ( 㬠)

bit#  7 6 5 4 3 2 1 0
      x x x N N N N N

 4-0       㬠   ⠪
         ࠧ  0  31 (筮).
-------------------------------------------------------------------------------

ଠ ॣ R7 (Mixer):

bit# 7 6 | 5 4 3 | 2 1 0
         | Noise | Melody
     x x | C B A | C B A

᫨  5 = 0 -   C 
᫨  4 = 0 -   B 
᫨  3 = 0 -   A 

᫨  2 = 0 -  C ࠥ 
᫨  1 = 0 -  B ࠥ 
᫨  0 = 0 -  A ࠥ 

     騬 ६. ஬ 㬠 ᮮ-
 ஬ ⮭ (. ॣ 08, 09, 0A).  㬠 
     ॣ 06    । 0-31 (.
ॣ. 06). ᫨  -   몫祭   ,  ᮮ⢥-
騩  ॣ ஬  ࠢ ஢ 殮  室.
砥 - ⨯ 4-⭮ 䬨᪮ Covox-.  ࠧ
 ந ஢  -   8- ""
 Scream Tracker ॡ ८ࠧ  4- 䬨᪨ .
-------------------------------------------------------------------------------

ଠ ॣ஢ 08, 09, 0A (஬ ):

bit#  7 6 5 4 3 2 1 0
      x x x E V V V V

 3-0 - ஬  (0-, 15-). ஬   -
           ᪮ 誠   㬥襭 ᫠  2 뢠 㬥襭
           ஬  2 ࠧ.

 4    - ⠭ envelope ()  .  ⠭ -
           饩 ࠢ ஬ । AY.  ⮬ ஬
             ६ ᮣ᭮   ॣ 0D ଥ
           饩,  ਮ ()    ॣ 0B 
           0C.
-------------------------------------------------------------------------------

ଠ ॣ 0B ( 8  ਮ 饩)

bit#  7 6 5 4 3 2 1 0
      L L L L L L L L
-------------------------------------------------------------------------------

ଠ ॣ 0C (孨 4  ਮ 饩)

bit#  7 6 5 4 3 2 1 0
      x x x x H H H H
-------------------------------------------------------------------------------

ଠ ॣ 0D (ଠ 饩)

bit#  7 6 5 4 3 2 1 0
      x x x x S S S S

 3-0  -   (shape)  ஬  .

-------------------------------------------------------------------------------
