/*!***************************************************************************** ******************************************************************************* \note d2a_NI6259 \date Dec 2009 \remarks set the digital-to-analog (d2a) on a particular channel to a particiular value, expressed as a percentage value of the max range of the D/A converter. Using percentage values frees the user from knowing the resolution of the D/A converter. Note that we have a 16bit d2a channel on this board. ******************************************************************************* Function Parameters: [in]=input,[out]=output \param[in] channel : which channel to use (numbered from 1 onwards) \param[in] pval : [0 to 100] percentage value of max range to be displayed. ******************************************************************************/ int d2a_NI6259(int channel, double pval) { char buf[2]; int val = 65535; int rc; static int count_calls=0; static int count_errors=0; /* if (++count_calls%100000 == 0) printf("%d %d\n",count_calls,count_errors); */ // create the fractional value val *= pval/100.; // copy to char array (2 bytes) memcpy(buf,(void *)&val,2); // the real channel count starts at zero channel -= 1; // send to the channel of the device //semTake(sm_init_process_ready_sem,WAIT_FOREVER); //a4l_snd_cancel(&desc,SUBDEV_AO); rc = a4l_sync_write(&desc,SUBDEV_AO,CHAN(channel), 0,buf, 2); //semGive(sm_init_process_ready_sem); if (rc < 0) { if (rc == -16) ++count_errors; else printf("d2a_NI6259: error in a4l_sync_write (rc=%d)\n",rc); return FALSE; } return TRUE; }
int main(int argc, char *argv[]) { int err = 0; unsigned int cnt = 0; a4l_desc_t dsc = { .sbdata = NULL }; a4l_sbinfo_t *sbinfo; a4l_chinfo_t *chinfo; a4l_rnginfo_t *rnginfo; int (*dump_function) (a4l_desc_t *, unsigned char *, int) = dump_text; /* Compute arguments */ while ((err = getopt_long(argc, argv, "vrd:s:S:c:R:y:wh", insn_read_opts, NULL)) >= 0) { switch (err) { case 'v': verbose = 1; break; case 'd': filename = optarg; break; case 's': idx_subd = strtoul(optarg, NULL, 0); break; case 'S': scan_size = strtoul(optarg, NULL, 0); break; case 'c': idx_chan = strtoul(optarg, NULL, 0); break; case 'R': idx_rng = strtoul(optarg, NULL, 0); dump_function = dump_converted; break; case 'w': dump_function = dump_raw; break; case 'y': dump_function = dump_calibrated; calibration_file = optarg; break; case 'h': default: do_print_usage(); return 0; } } if (isatty(STDOUT_FILENO) && dump_function == dump_raw) { fprintf(stderr, "insn_read: cannot dump raw data on a terminal\n\n"); return -EINVAL; } /* Open the device */ err = a4l_open(&dsc, filename); if (err < 0) { fprintf(stderr, "insn_read: a4l_open %s failed (err=%d)\n", filename, err); return err; } if (verbose != 0) { printf("insn_read: device %s opened (fd=%d)\n", filename, dsc.fd); printf("insn_read: basic descriptor retrieved\n"); printf("\t subdevices count = %d\n", dsc.nb_subd); printf("\t read subdevice index = %d\n", dsc.idx_read_subd); printf("\t write subdevice index = %d\n", dsc.idx_write_subd); } /* Allocate a buffer so as to get more info (subd, chan, rng) */ dsc.sbdata = malloc(dsc.sbsize); if (dsc.sbdata == NULL) { err = -ENOMEM; fprintf(stderr, "insn_read: info buffer allocation failed\n"); goto out_insn_read; } /* Get this data */ err = a4l_fill_desc(&dsc); if (err < 0) { fprintf(stderr, "insn_read: a4l_fill_desc failed (err=%d)\n", err); goto out_insn_read; } if (verbose != 0) printf("insn_read: complex descriptor retrieved\n"); /* If no subdevice index was set, look for an analog input subdevice */ if (idx_subd == -1) idx_subd = dsc.idx_read_subd; if (idx_subd == -1) { fprintf(stderr, "insn_read: no analog input subdevice available\n"); err = -EINVAL; goto out_insn_read; } if (verbose != 0) printf("insn_read: selected subdevice index = %d\n", idx_subd); /* We must check that the subdevice is really an AI one (in case, the subdevice index was set with the option -s) */ err = a4l_get_subdinfo(&dsc, idx_subd, &sbinfo); if (err < 0) { fprintf(stderr, "insn_read: get_sbinfo(%d) failed (err = %d)\n", idx_subd, err); err = -EINVAL; goto out_insn_read; } if ((sbinfo->flags & A4L_SUBD_TYPES) != A4L_SUBD_AI) { fprintf(stderr, "insn_read: wrong subdevice selected " "(not an analog input)\n"); err = -EINVAL; goto out_insn_read; } if (idx_rng >= 0) { err = a4l_get_rnginfo(&dsc, idx_subd, idx_chan, idx_rng, &rnginfo); if (err < 0) { fprintf(stderr, "insn_read: failed to recover range descriptor\n"); goto out_insn_read; } if (verbose != 0) { printf("insn_read: range descriptor retrieved\n"); printf("\t min = %ld\n", rnginfo->min); printf("\t max = %ld\n", rnginfo->max); } } /* Retrieve the subdevice data size */ err = a4l_get_chinfo(&dsc, idx_subd, idx_chan, &chinfo); if (err < 0) { fprintf(stderr, "insn_read: info for channel %d on subdevice %d not available (err=%d)\n", idx_chan, idx_subd, err); goto out_insn_read; } /* Set the data size to read */ scan_size *= a4l_sizeof_chan(chinfo); if (verbose != 0) { printf("insn_read: channel width is %u bits\n", chinfo->nb_bits); printf("insn_read: global scan size is %u\n", scan_size); } while (cnt < scan_size) { int tmp = (scan_size - cnt) < BUF_SIZE ? (scan_size - cnt) : BUF_SIZE; /* Perform the synchronous read */ err = a4l_sync_read(&dsc, idx_subd, CHAN(idx_chan), 0, buf, tmp); if (err < 0) { fprintf(stderr, "insn_read: a4l_sync_read failed (err=%d)\n", err); goto out_insn_read; } /* Dump the read data */ tmp = dump_function(&dsc, buf, err); if (tmp < 0) { err = tmp; goto out_insn_read; } /* Update the count */ cnt += err; } if (verbose != 0) printf("insn_read: %u bytes successfully received\n", cnt); err = 0; out_insn_read: /* Free the information buffer */ if (dsc.sbdata != NULL) free(dsc.sbdata); /* Release the file descriptor */ a4l_close(&dsc); return err; }