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#include "memory.h"
#include <stdio.h>
void memory_init( memory_t *memory, seg7_t *seg )
{
memory->read = memory_read;
memory->write = memory_write;
memory->seg = seg;
}
uint8_t memory_read( memory_t *memory, uint16_t addr )
{
if( addr <= 0x3FFF ) {
// RAM access
return memory->cell[addr];
} else if( addr <= 0x8000 ) {
return seg7_read( memory->seg, addr );
} else {
// ROM access
return memory->cell[addr];
}
}
void memory_write( memory_t *memory, uint16_t addr, uint8_t data )
{
if( addr <= 0x3FFF ) {
// RAM access
memory->cell[addr] = data;
} else if( addr <= 0x8000 ) {
seg7_write( memory->seg, addr, data );
} else {
// ignore writes to ROM
}
}
void memory_load( memory_t *memory, uint16_t addr, uint16_t size, const char *filename )
{
if( addr >= 0x8000 ) {
FILE *f = fopen( filename, "rb" );
if( f == NULL ) {
fprintf( stderr, "ERROR: Unable to open ROM file '%s'\n", filename );
exit( EXIT_FAILURE );
}
fread( &memory->cell[addr], size, 1, f );
fclose( f );
fprintf( stderr, "INFO: Loaded firware from '%s' of size %d starting on address %04X\n",
filename, size, addr );
} else {
fprintf( stderr, "ERROR: Cannot load firmware into RAM at address %04X\n", addr );
}
}
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