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modified to work with TRIG_INT, made it use the -F command line option to

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set update frequency
This commit is contained in:
Frank Mori Hess 2001-08-24 19:08:55 +00:00
parent b00e1eb5bd
commit ea27e98235
1 changed files with 17 additions and 12 deletions
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29
demo/ao_waveform.c
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@ -58,10 +58,6 @@
/* frequency of the sine wave to output */ /* frequency of the sine wave to output */
double waveform_frequency = 100.0; double waveform_frequency = 100.0;
/* update rate for the DAC, typically much higher than
the frequency of the sine wave. */
double update_frequency = 50000.0;
/* peak-to-peak amplitude, in DAC units (i.e., 0-4095) */ /* peak-to-peak amplitude, in DAC units (i.e., 0-4095) */
double amplitude = 4000; double amplitude = 4000;
@ -91,6 +87,7 @@ void dds_init_sawtooth(void);
int main(int argc, char *argv[]) int main(int argc, char *argv[])
{ {
comedi_cmd cmd; comedi_cmd cmd;
comedi_insn insn;
int err; int err;
int n,m; int n,m;
int total=0; int total=0;
@ -104,16 +101,19 @@ int main(int argc, char *argv[])
} }
dev = comedi_open(filename); dev = comedi_open(filename);
if(dev == NULL){
fprintf(stderr, "error opening %s\n", filename);
return -1;
}
subdevice = comedi_find_subdevice_by_type(dev,COMEDI_SUBD_AO,0); subdevice = comedi_find_subdevice_by_type(dev,COMEDI_SUBD_AO,0);
memset(&cmd,0,sizeof(cmd)); memset(&cmd,0,sizeof(cmd));
cmd.subdev = subdevice; cmd.subdev = subdevice;
cmd.flags = 0; cmd.flags = 0;
cmd.start_src = TRIG_NOW; cmd.start_src = TRIG_INT;
cmd.start_arg = 0; cmd.start_arg = 0;
cmd.scan_begin_src = TRIG_TIMER; cmd.scan_begin_src = TRIG_TIMER;
cmd.scan_begin_arg = 1e9/update_frequency; cmd.scan_begin_arg = 1e9/freq;
cmd.convert_src = TRIG_NOW; cmd.convert_src = TRIG_NOW;
cmd.convert_arg = 0; cmd.convert_arg = 0;
cmd.scan_end_src = TRIG_COUNT; cmd.scan_end_src = TRIG_COUNT;
@ -131,14 +131,19 @@ int main(int argc, char *argv[])
dds_output(data,BUF_LEN); dds_output(data,BUF_LEN);
dds_output(data,BUF_LEN); dds_output(data,BUF_LEN);
m=write(comedi_fileno(dev),data,BUF_LEN*sizeof(sampl_t));
perror("write");
printf("m=%d\n",m);
if ((err = comedi_command(dev, &cmd)) < 0) { if ((err = comedi_command(dev, &cmd)) < 0) {
comedi_perror("comedi_command"); comedi_perror("comedi_command");
exit(1); exit(1);
} }
m=write(comedi_fileno(dev),data,BUF_LEN*sizeof(sampl_t));
perror("write");
printf("m=%d\n",m);
memset(&insn, 0, sizeof(comedi_insn));
insn.insn = INSN_INTTRIG;
comedi_do_insn(dev, &insn);
while(1){ while(1){
dds_output(data,BUF_LEN); dds_output(data,BUF_LEN);
n=BUF_LEN*sizeof(sampl_t); n=BUF_LEN*sizeof(sampl_t);
@ -174,7 +179,7 @@ void dds_init(void)
{ {
int i; int i;
adder=waveform_frequency/update_frequency*(1<<16)*(1<<WAVEFORM_SHIFT); adder=waveform_frequency/freq*(1<<16)*(1<<WAVEFORM_SHIFT);
dds_init_function(); dds_init_function();