Stanford Research Systems DS345, Manual

Page: 69 / 139

Program Examples
3-19
/* since list is of phase CHANGES need to calculate initial phase of
waveform and then calculate phase shifts */
old = 0.0; /* initial sine wave value = 0 = sin (0) */
/* calculate 4-byte data values. each value = 2^16 * delta phase */
for (i = 0 ; i < number ; i++)
{
new = span * sin ((6.2831853*(double)(i+1))/(double)number)/2.0;/*new phase */
t = new - old; /* phase change */
old = new; /* save new phase for next time */
data[i] = (long)(s*t);
sum += data[i]; /* update checksum */
}
data[number] = sum; /* store checksum */
sprintf (cmd,"MENA0;MTYP4;MDWF5\n"); /* make sure modulation off until after
loading, set PM, arb WF */
ibwrt (ds345,cmd,strlen(cmd)); /* send commands */
sprintf (cmd,"AMOD?%d\n",number); /* arb modulation command */
ibwrt (ds345,cmd,strlen(cmd));
ibrd (ds345,cmd,40); /* read back reply before sending data */
ibwrt (ds345,(char *)data,(long)4*4); /* number of bytes = 4 per data
point + 4 for checksum */
sprintf (cmd,"MENA1\n"); /* turn modulation on */
ibwrt (ds345,cmd,strlen(cmd));
}
EXAMPLE 4: Point Mode Arbitrary Waveform.
This program downloads an arbitrary in point edit mode. The data is just a list of the amplitude value at each
waveform RAM point. The program is written in C.
/* program to donwload point mode arb wf to DS345.
The waveform is a simple ramp. Written in
Microsoft C and uses National Instrument GPIB card. Expects DS345
to be installed as DS345 in IBCONF */
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <dos.h>
#include <decl.h> /* National Instruments header file */
void main(void);
int ds345;
int data[10000]; /* up to 10000 points */
void main ()
{
char cmd[40];
int i,sum,j,number;