Agilent Technologies E8663B, N5183A Creating and Downloading Waveform Files Programming Examples

Creating and Downloading Waveform Files

Programming Examples

//0 gives 0 V output

//32767 gives positive full-scale output

//From these ranges, it appears you should offset the

//data by 8192 and scale it by 4. However, due to the

//interpolators in these products, it is better to scale

//the data by a number less than four. Commonly a good

//choice is 70% of 4 which is 2.8.

//By default, the signal generator scales data to 70%

//If you scale the data here, you may want to change the

//signal generator scaling to 100%

//Also we need to swap the byte order on a little endian

//computer. This code also works for big endian order data

//since it swaps bytes based on the order.

for(index=0; index<numsamples; index++)
{
int iscaled = 2.8*(idata[index]-8192);		// shift	and scale
int qscaled = 2.8*(qdata[index]-8192);		// shift	and scale
iqbuffer[index*4]	= (iscaled >> 8) &	0xFF; //	high byte of i
iqbuffer[index*4+1] = iscaled & 0xFF;		//	low byte of i
iqbuffer[index*4+2] = (qscaled >> 8) &		0xFF; //	high byte of q
iqbuffer[index*4+3] = qscaled & 0xFF;		// low byte of q
}

//Open a connection to write to the instrument INST id=iopen(instOpenString);

if (!id)

{

fprintf(stderr, “iopen failed (%s)\n”, instOpenString); return -1;

}

//Declare variables which will be used later

int bytesToSend; char s[20]; char cmd[200];

//The E4438C, E8267C and E8267D accept the E443xB format.

//so we can use this next section on any of these signal generators.

//However the E443xB format only uses 14 bits.

bytesToSend = numsamples*2; // calculate the number of bytes

sprintf(s, “%d”, bytesToSend); // create a string s with that number of bytes

Agilent N518xA, E8663B, E44x8C, and E82x7D Signal Generators Programming Guide 253