/* reads/writes a byte; write_value is -1 for read only */
static UINT8 apple525_process_byte(mess_image *img, int write_value)
{
UINT8 read_value;
struct apple525_disk *disk;
int spinfract_divisor;
int spinfract_dividend;
const struct IODevice *dev;
disk = (struct apple525_disk *) image_lookuptag(img, APPLE525TAG);
dev = image_device(img);
spinfract_dividend = (int) device_get_info_int(&dev->devclass, DEVINFO_INT_APPLE525_SPINFRACT_DIVIDEND);
spinfract_divisor = (int) device_get_info_int(&dev->devclass, DEVINFO_INT_APPLE525_SPINFRACT_DIVISOR);
/* no image initialized for that drive ? */
if (!image_exists(img))
return 0xFF;
/* check the spin count if reading*/
if (write_value < 0)
{
disk->spin_count++;
disk->spin_count %= spinfract_divisor;
if (disk->spin_count >= spinfract_dividend)
return 0x00;
}
/* load track if need be */
if (disk->track_loaded == 0)
apple525_load_current_track(img);
/* perform the read */
read_value = disk->track_data[disk->position];
/* perform the write, if applicable */
if (write_value >= 0)
{
disk->track_data[disk->position] = write_value;
disk->track_dirty = 1;
}
disk->position++;
disk->position %= (sizeof(disk->track_data) / sizeof(disk->track_data[0]));
/* when writing; save the current track after every full sector write */
if ((write_value >= 0) && ((disk->position % APPLE2_NIBBLE_SIZE) == 0))
apple525_save_current_track(img, FALSE);
return read_value;
}
/* reads/writes a byte; write_value is -1 for read only */
static UINT8 apple525_process_byte(device_t *img, int write_value)
{
UINT8 read_value;
apple525_floppy_image_device *disk;
int spinfract_divisor;
int spinfract_dividend;
apple525_floppy_image_device *config = get_device(img);
device_image_interface *image = dynamic_cast<device_image_interface *>(img);
disk = get_device(img);
spinfract_dividend = config->get_dividend();
spinfract_divisor = config->get_divisor();
/* no image initialized for that drive ? */
if (!image->exists())
return 0xFF;
/* check the spin count if reading*/
if (write_value < 0)
{
disk->spin_count++;
disk->spin_count %= spinfract_divisor;
if (disk->spin_count >= spinfract_dividend)
return 0x00;
}
/* load track if need be */
if (disk->track_loaded == 0)
apple525_load_current_track(img);
/* perform the read */
read_value = disk->track_data[disk->position];
/* perform the write, if applicable */
if (write_value >= 0)
{
disk->track_data[disk->position] = write_value;
disk->track_dirty = 1;
}
disk->position++;
disk->position %= ARRAY_LENGTH(disk->track_data);
/* when writing; save the current track after every full sector write */
if ((write_value >= 0) && ((disk->position % APPLE2_NIBBLE_SIZE) == 0))
apple525_save_current_track(img, FALSE);
return read_value;
}
