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#ifndef VIA_6522_H
#define VIA_6522_H

#include "device.h"
#include "bus.h"

#include <stdint.h>
#include <stdbool.h>

#ifdef WITH_GUI
#include <SDL.h>
#endif

// the VIA connects to sub-devices itself via the bus. It also
// has things like timers and internal registers
// the VIA is initialized with a base address, the addresses for
// the registers are relative to this base.
enum {
	PORTB = 0x00,
	PORTA = 0x01,
	DDRB  = 0x02,
	DDRA  = 0x03,
	T1LCL = 0x04,
	T1LCH = 0x05,
	ACR   = 0x0b,
	PCR   = 0x0c,
	IFR   = 0x0d,
	IER   = 0x0e
};

typedef struct via_6522_t
{
	device_t base;
	
	uint16_t addr;
	
	uint8_t ddra;
	uint8_t ddrb;
	uint8_t pcr;
	uint8_t ier;

	bool debug;
	
	bus_t busa;
	bus_t busb;
} via_6522_t;

void via_6522_init( via_6522_t *via, uint16_t addr, bool initialize );
void via_6522_reset( via_6522_t *via );
void via_6522_register( via_6522_t *via, int bus, device_t *device );

uint8_t via_6522_read( void *obj, uint16_t addr );
void via_6522_write( void *obj, uint16_t addr, uint8_t data );
#ifdef WITH_GUI
void via_6522_draw( void *obj, SDL_Renderer *renderer );
#endif
void via_6522_deinit( void *obj );

#endif