Spectrum Brands MI.61XX manual Sample format, Standard mode, Bit Standard Mode

Programming Standard generation modes

Standard mode

Writing data to the memory is really easy, if a replay mode is used, that stores non multiplexed data in the dedicated memory channels. The next example shows, how to write the data before replaying two channels without multiplexing to both memory channels.

for (i = 0; i < 2; i++)	// both memory channels have been used
pbyData[i] = (ptr8) malloc (lMemsize);	// allocate memory for the data pointers
// generate or load data into pbyData[0..1]	// with the maximum size (lMemsize)
SpcSetData (hDrv, 0, 0, lMemsize, (dataptr) pbyData[0]);	// no multiplexing is necessary on channel 0
SpcSetData (hDrv, 1, 0, lMemsize, (dataptr) pbyData[1]);	// neither it is on channel 1

If you use two channels for replay using only one memory channel, the data in the memory channel(s) has to be multiplexed and needs to be sorted by the user. The following example shows how to sort the data for the replay of two channels using memory channel 0.

for (i = 0; i < 2; i++)		// two channels to write to memory channel 0
pbyData[i] = (ptr8) malloc (lMemsize);		// allocate memory for the data pointers
		// with the maximum size (lMemsize) per channel
// generate or load data into pbyData[0..1]
pbyTmp = (ptr8) malloc (lMemsize * 2);		// allocate temporary buffer for copy
for (i = 0; i < lMemsize; i++)		// combine data of the two channels
{	= pbyData[0][i];
pbyTmp[2*i]
pbyTmp[2*i+1] = pbyData[1][i];
}
SpcSetData (hDrv, 0, 0, 2 * lMemsize, (dataptr) pbyTmp);		// write both channels to memory channel 0
free (pbyTmp);		// free the temporary buffer

Sample format

The 8 bit samples in twos complement are always stored in memory 16 bit integer values. This leads to a range of possible integer values from -128…0…+127.

Bit	Standard Mode
D7	DAx Bit 7 (MSB)
D6	DAx Bit 6
D5	DAx Bit 5
D4	DAx Bit 4
D3	DAx Bit 3
D2	DAx Bit 2
D1	DAx Bit 1
D0	DAx Bit 0 (LSB)

48 MI.61xx Manual