PIA on a Breadboard

[UNIXcoffee928]

This thread is for describing methods of accurately reverse-engineering the PIA, so that it may first be described & documented on a breadboard, and then, may be used to facilitate a model that can be used in a FPGA description language.

 

This idea came to life in the "Atari on a Breadboard" thread, but will be treated as a separate concept, to keep the threads from becoming distracting & cluttered.

 

Here are the links to all related threads in this "Brute Force Initiative":

 

- Atari on a Breadboard

- POKEY on a Breadboard

- ANTIC on a Breadboard

- SALLY on a Breadboard

- GTIA on a Breadboard

- PIA on a Breadboard

 

=========================================================
PIA
=========================================================
           _________
          |   | |   |
          |    -    |
01. Vss   -| 01   40 |- 40. CA1
02. PA0   -| 02   39 |- 39. CA2
03. PA1   -| 03   38 |- 38. IRQA
04. PA2   -| 04   37 |- 37. IRQB
05. PA3   -| 05   36 |- 36. A1
06. PA4   -| 06   35 |- 35. A0
07. PA5   -| 07   34 |- 34. RST
08. PA6   -| 08   33 |- 33. D0
09. PA7   -| 09   32 |- 32. D1
10. PB0   -| 10   31 |- 31. D2
11. PB1   -| 11   30 |- 30. D3
12. PB2   -| 12   29 |- 29. D4
13. PB3   -| 13   28 |- 28. D5
14. PB4   -| 14   27 |- 27. D6
15. PB5   -| 15   26 |- 26. D7
16. PB6   -| 16   25 |- 25. Ø2
17. PB7   -| 17   24 |- 24. CS1
18. CB1   -| 18   23 |- 23. CS2
19. CB2   -| 19   22 |- 22. CS0
20. Vcc   -| 20   21 |- 21. R/W
          |_________|
          |   PIA   |
          |_________|

 

=========================================================
PIA (Pins run 0-20 on left & 40-21 on the right)
=========================================================
01. Vss:    Ground
02. PA0:    Bidirectional port A 0 (stick direction, paddle triggers, etc.)
03. PA1:    Bidirectional port A 1 (stick direction, paddle triggers, etc.) 
04. PA2:    Bidirectional port A 2 (stick direction, paddle triggers, etc.) 
05. PA3:    Bidirectional port A 3 (stick direction, paddle triggers, etc.) 
06. PA4:    Bidirectional port A 4 (stick direction, paddle triggers, etc.) 
07. PA5:    Bidirectional port A 5 (stick direction, paddle triggers, etc.) 
08. PA6:    Bidirectional port A 6 (stick direction, paddle triggers, etc.) 
09. PA7:    Bidirectional port A 7 (stick direction, paddle triggers, etc.)
10. PB0:    Bidirectional port B 0 (stick direction, paddle triggers, etc.)
11. PB1:    Bidirectional port B 1 (stick direction, paddle triggers, etc.)
12. PB2:    Bidirectional port B 2 (stick direction, paddle triggers, etc.)
13. PB3:    Bidirectional port B 3 (stick direction, paddle triggers, etc.)
14. PB4:    Bidirectional port B 4 (stick direction, paddle triggers, etc.)
15. PB5:    Bidirectional port B 5 (stick direction, paddle triggers, etc.)
16. PB6:    Bidirectional port B 6 (stick direction, paddle triggers, etc.)
17. PB7:    Bidirectional port B 7 (stick direction, paddle triggers, etc.)
18. CB1:    Port B control
19. CB2:    Port B control
20. Vcc:    +5V power
21. R/W:    Read/write direction
22. CS0:    Chip Select
23. CS2:    Chip Select (active low)
24. CS1:    Chip Select
25. Ø2:     Sync
26. D7:     Data bus         7
27. D6:     Data bus         6
28. D5:     Data bus         5
29. D4:     Data bus         4
30. D3:     Data bus         3
31. D2:     Data bus         2
32. D1:     Data bus         1
33. D0:     Data bus         0
34. RST:    Chip reset
35. A0:     Addr bus         0
36. A1:     Addr bus         1
37. IRQB:   Port B interrupt line
38. IRQA:   Port A interrupt lines
39. CA2:    Port A control
40. CA1:    Port A control

 

 

Welcome Aboard!

 

Edited November 5, 2008 by UNIXcoffee928

[Rybags]

PIA workalikes are still alive and available today.

 

Probably not worth trying to duplicate the functions of something available off the shelf for a few bucks.