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#include "7seg.h"
#include <stdio.h>
static device_vtable_t const seg7_vtable = {
seg7_read,
seg7_write,
seg7_deinit
};
void seg7_init( seg7_t *seg, uint16_t addr, bool initialize )
{
device_init( &seg->base, "seg7" );
seg->base.vtable = (device_vtable_t *)&seg7_vtable;
seg->addr = addr;
seg->debug = false;
if( initialize ) {
seg->latch = 0x0000;
seg->shift = 0x0000;
}
}
uint8_t seg7_read( void *obj, uint16_t addr )
{
return 0;
}
void seg7_write( void *obj, uint16_t addr, uint8_t data )
{
seg7_t *seg = (seg7_t *)obj;
switch( addr - seg->addr ) {
case DDRA:
seg->ddr = data;
break;
case PORTA:
// write bits from SER into shift register on positive SRCLK
if( ( seg->ddr | ( SRCLK & SER ) ) && ( data & SRCLK ) ) {
seg->shift = ( seg->shift << 1 ) | ( data & SER );
if( seg->debug ) {
fprintf( stderr, "7seg shifting data, data is now %02X\n", seg->shift );
}
}
// copy shift to latch register on positive RCLK
if( ( seg->ddr | RCLK ) && ( data & RCLK ) ) {
seg->latch = seg->shift;
if( seg->debug ) {
fprintf( stderr, "7seg copying %02X from shift to latch\n", seg->latch );
}
}
break;
// ignore writes to other addresses
}
}
void seg7_deinit( void *obj )
{
seg7_t *seg = (seg7_t *)obj;
device_deinit( &seg->base );
}
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