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#include "6522.h"
#include <stdio.h>
#include <stdbool.h>
static device_vtable_t const via_6522_vtable = {
via_6522_read,
via_6522_write,
#ifdef WITH_GUI
via_6522_draw,
#endif
via_6522_deinit
};
void via_6522_init( via_6522_t *via, uint16_t addr, bool initialize )
{
device_init( &via->base, "via_6522" );
via->base.vtable = (device_vtable_t *)&via_6522_vtable;
via->addr = addr;
via->debug = false;
if( initialize ) {
via->ddra = 0x00;
via->ddrb = 0x00;
via->pcr = 0x00;
via->ier = 0x00;
}
bus_init( &via->busa );
bus_init( &via->busb );
}
void via_6522_reset( via_6522_t *via )
{
via->ddra = 0x00;
via->ddrb = 0x00;
via->pcr = 0x00;
via->ier = 0x00;
}
void via_6522_register( via_6522_t *via, int bus, device_t *device )
{
switch( bus ) {
case PORTA:
bus_register( &via->busa, device, 0, 0 );
break;
case PORTB:
bus_register( &via->busb, device, 0, 0 );
break;
default:
fprintf( stderr, "ERROR: unable to register to VIA 6522 bus, use PORTA or PORTB\n" );
}
}
uint8_t via_6522_read( void *obj, uint16_t addr )
{
return 0;
}
void via_6522_write( void *obj, uint16_t addr, uint8_t data )
{
via_6522_t *via = (via_6522_t *)obj;
switch( addr - via->addr ) {
case PORTA:
data &= via->ddra;
for( int i = 0; i < via->busa.nof_devices; i++ ) {
device_t *device = via->busa.devices[i].device;
device->vtable->write( device, 0, data );
}
break;
case PORTB:
data &= via->ddrb;
for( int i = 0; i < via->busb.nof_devices; i++ ) {
device_t *device = via->busb.devices[i].device;
device->vtable->write( device, 0, data );
}
break;
case DDRB:
via->ddrb = data;
break;
case DDRA:
via->ddra = data;
break;
case PCR:
via->pcr = data;
break;
case IER:
via->ier = data;
break;
default:
fprintf( stderr, "ERROR: VIA 6522 not implemented address '%04X', data: '%02X'\n", addr, data );
break;
}
}
#ifdef WITH_GUI
void via_6522_draw( void *obj, SDL_Renderer *renderer )
{
via_6522_t *via = (via_6522_t *)obj;
via->busa.base.vtable->draw( &via->busa, renderer );
via->busb.base.vtable->draw( &via->busb, renderer );
}
#endif
void via_6522_deinit( void *obj )
{
via_6522_t *via = (via_6522_t *)obj;
bus_deinit( &via->busa );
bus_deinit( &via->busb );
device_deinit( &via->base );
}
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