C02/include/via.h02

/* MOS 6522 VIA Registers */

struct via {
  char iorb; //Input/Output Register B
  char iora; //Input/Output Register A
  char ddrb; //Data Direction Register B
  char ddra; // Data Direction Register A
  char t1cl; //T1 Low-Order Counter
  char t1ch; //T1 High-Order Counter
  char t1ll; //T1L-L | T1 Low-Order Latches
  char t1lh; //T1 High-Order Latches
  char t2cl; //T2 Low-Order Latches
  char t2ch; //T2 High-Order Counter
  char sr; //Shift Register
  char acr; //Auxiliary Control Register
  char pcr; //Peripheral Control Register
  char ifr; //Interrupt Flag Register
  char ier; //Interrupt Enable Register
  char nhra; //Input/Output Register A (No Handshake)
}