 
 
 
                       ஫  ᪮                         
 
 ࠧ 뢠 /  ஫ FDC. ᭮   -
NEC mPD765 ( ᮢ⨬  FDC).

஫ AT FDC ࠧ饭  ⮩  ,   ஫ , 
ᮢ⨬  ⠭ oPC/XTo FDC (᪫ ,  ७ ).
᭮ ࠧ  ⮬,  AT FDC ᪠ ᪮쪮 ᪮⥩ ।,
 ন ⮫쪮  ன⢠.

      o ஫ ᪥ 1   3f0H..3f7H
      o ஫ ᪥ 2   370H..377H (⮫쪮 AT )

FDC  뢠 ஢ 6 (IRQ 6) ᫥  樨 (⥭,
,   ..). IRQ 6   INT 0eH  ࠡ뢠 BIOS.

  ᠭ
  
3f2H  : ஢ 室 ॣ
      76543210
      |D C B A| | |   |
      ------ 
       \====/ | | \==> 0-1:  ன⢮ 0-3 (AT:  1  ᯮ.)
          |    | \=====> 2: 0= ஫; 1=祭 ஫
          |    \=======> 3: 1=ࠧ DMA  뢠  ᪥
          \==========> 4-7:   ( ᮮ⢥ ன⢠).
                            (AT:  6-7  ᯮ)
3f4H  쪮 ⥭:  ॣ 
      76543210
      | | | | |D C B A|
      ---- 
       | | | | \======> 0: ன⢮  (AT:  2-3  .)
       | | | \=========> 4: 1=஫  ( ⥭  )
       | | \===========> 5: 1= DMA; 0=⨢ ० DMA
       | \=============> 6: ࠢ ।: 1 = FDC=>CPU; 0 = CPU=>FDC
       \===============> 7:  Master. 1= ਭ/।

3f5H  ⥭/: ॣ / FDC
        ᯮ    ஫.  뢮
       , ⥬ 뢮   ᪮쪮  ࠬ஢.
      ᫥ 믮 樨     ᪮쪨 
      १.   -뢮 ⢫ १  
        ᮡ ࠢ ᫥⥫쭮.

       ਢ , ᯮ㥬 ⠭묨 㭪ﬨ BIOS, 
        ࠬ    祭  १⮢.
          㪮 Tech Ref, ᫨  㧭 .

        ᠭ
        
      e6H    (ਭ 8 ࠬ஢; 7  १)
      c5H    (ਭ 8 ࠬ஢; 7  १)
      4dH  ଠ஢ ஦ (ਭ 5 ࠬ஢; 7  १)
      07H   (ਭ 1 ࠬ;   १)
      0fH  ᪠ ஦ (ਭ 2 ࠬ;   १)

3f6H  AT  : ॣ 䨪஢ ᪠ ( ᢥ)
 
 
 
                       ஫  ᪮            ...த
 
3f7H  AT  : ॣ ࠢ ᪥⮩
      76543210
      |           |   |
      -------- 
       \========/ \==> 0-1: ᪮ । 
            |                 00=500 KBS, 01=300 KBS, 10=250 KBS, 11=१
            \==========> 2-7:   ᬮ  祣   

      ⥭: ஢ ॣ . .  ⨪ (஬  7)
      76543210
      |c| |       | | |
      ----ҽ 
       | | \====/ | \=> 0: 1= . 0
       | |    |    \===> 1: 1= . 1
       | |    \======> 2-5:   0-3 (2=.0,3=.1, etc)
       | \=============> 6:  
       \===============> 7: "Change Line" (1=ᬥ ᪥)
------------------------------------------------------------------------------
 INT 13H   㭪樨 ROM-BIOS                                    ⮢ /
