6821

Peripheral Interface Adapter PIA

Pinout

DIP40
        +---\/---+
    Vss | 1    40| CA1
    PA0 | 2    39| CA2
    PA1 | 3    38| *IRQA
    PA2 | 4    37| *IRQB
    PA3 | 5    36| RS0
    PA4 | 6    35| RS1
    PA5 | 7    34| *RESET
    PA6 | 8    33| D0
    PA7 | 9    32| D1
    PB0 |10    31| D2
    PB1 |11    30| D3
    PB2 |12    29| D4
    PB3 |13    28| D5
    PB4 |14    27| D6
    PB5 |15    26| D7
    PB6 |16    25| E
    PB7 |17    24| CS1
    CB1 |18    23| *CS2
    CB2 |19    22| CS0
    Vcc |20    21| R/*W
        +--------+

Frequency

No frequency to check

External links

"6809 support chips" page on CPU-World

Files

• 
  MC6821 Datasheet
• 
  EF6821 Datasheet