demo/receiver.c

   1 /*
   2  * Digital I/O example
   3  * Part of Comedilib
   4  *
   5  * Copyright (c) 1999,2000 David A. Schleef <ds@schleef.org>
   6  *
   7  * This file may be freely modified, distributed, and combined with
   8  * other software, as long as proper attribution is given in the
   9  * source code.
  10  */
  11 /*
  12  * Requirements:  A board with a digital I/O subdevice.  Not just
  13  *    a 'digital input' or 'digital output' subdevice, but one in
  14  *    which the channels can be configured between input and output.
  15  */
  16
  17 #define _GNU_SOURCE
  18
  19 #include <stdio.h>
  20 #include <comedilib.h>
  21 #include <fcntl.h>
  22 #include <unistd.h>
  23 #include <stdlib.h>
  24 #include <errno.h>
  25 #include <getopt.h>
  26 #include <ctype.h>
  27 #include <signal.h>
  28 #include <string.h>
  29 #include <sys/time.h>
  30 #include "examples.h"
  31
  32 int pin_clk = 2;
  33 int pin_data = 10;
  34
  35 comedi_t *device;
  36
  37 #define BUFSZ 1024
  38 sampl_t buf[BUFSZ];
  39
  40 void prepare_cmd(comedi_t *dev,comedi_cmd *cmd);
  41 void do_cmd(comedi_t *dev,comedi_cmd *cmd);
  42
  43 int main(int argc, char *argv[])
  44 {
  45         char *fn = NULL;
  46         comedi_t *dev;
  47         comedi_cmd cmd;
  48         int ret;
  49
  50         parse_options(argc,argv);
  51
  52         //fn = "/dev/comedi1";
  53         fn = "/dev/comedi0";
  54
  55         dev = comedi_open(fn);
  56         if(!dev){
  57                 perror(fn);
  58                 exit(1);
  59         }
  60         device = dev;
  61
  62         subdevice = 0;
  63
  64         if(channel)pin_data=channel;
  65
  66         ret = fcntl(comedi_fileno(dev),F_SETFL,O_NONBLOCK);
  67         if(ret<0)perror("fcntl");
  68
  69         prepare_cmd(dev,&cmd);
  70
  71         do_cmd(dev,&cmd);
  72
  73         return 0;
  74 }
  75
  76 static int c=0;
  77 static unsigned int bits =0;
  78
  79 void do_cmd(comedi_t *dev,comedi_cmd *cmd)
  80 {
  81         unsigned int *chanlist;
  82         int n_chans;
  83         int total=0;
  84         int ret;
  85         int go;
  86         struct timeval timeout;
  87         fd_set rdset;
  88
  89         chanlist = cmd->chanlist;
  90         n_chans = cmd->chanlist_len;
  91
  92         ret=comedi_command_test(dev,cmd);
  93
  94         //printf("test ret=%d\n",ret);
  95         if(ret<0){
  96                 printf("errno=%d\n",errno);
  97                 comedi_perror("comedi_command_test");
  98                 return;
  99         }
 100
 101         dump_cmd(stdout,cmd);
 102
 103         cmd->chanlist =         chanlist;
 104         cmd->chanlist_len =     n_chans;
 105
 106         ret=comedi_command_test(dev,cmd);
 107
 108         printf("test ret=%d\n",ret);
 109         if(ret<0){
 110                 printf("errno=%d\n",errno);
 111                 comedi_perror("comedi_command_test");
 112                 return;
 113         }
 114
 115         dump_cmd(stdout,cmd);
 116
 117         cmd->chanlist =         chanlist;
 118         cmd->chanlist_len =     n_chans;
 119
 120         ret=comedi_command(dev,cmd);
 121
 122         printf("ret=%d\n",ret);
 123         if(ret<0){
 124                 printf("errno=%d\n",errno);
 125                 comedi_perror("comedi_command");
 126                 return;
 127         }
 128
 129         go=1;
 130         while(go){
 131                 FD_ZERO(&rdset);
 132                 FD_SET(comedi_fileno(dev),&rdset);
 133                 timeout.tv_sec=0;
 134                 timeout.tv_usec=50000;
 135                 ret = select(comedi_fileno(dev)+1,&rdset,NULL,NULL,&timeout);
 136                 if(ret<0){
 137                         perror("select");
 138                 }else if(ret==0){
 139                         if(c){
 140                                 fprintf(stderr,"\n");
 141                                 c=0;
 142                                 bits=0;
 143                         }
 144                 }else if(FD_ISSET(comedi_fileno(dev),&rdset)){
 145                         ret=read(comedi_fileno(dev),buf,BUFSZ);
 146                         if(ret<0){
 147                                 if(errno==EAGAIN){
 148                                         go = 0;
 149                                         perror("read");
 150                                 }
 151                         }else if(ret==0){
 152                                 go = 0;
 153                         }else{
 154                                 int i;
 155
 156                                 total+=ret;
 157                                 for(i=0;i<ret/sizeof(sampl_t);i++){
 158                                         fprintf(stderr,"%d",buf[i]>0xa000);
 159                                         c++;
 160                                         if(c>=32){
 161                                                 fprintf(stderr,"\n");
 162                                                 c=0;
 163                                         }
 164 #if 0
 165                                         //printf("%d %d\n",buf[i],buf[i]>0xa000);
 166                                         //printf("%d",buf[i]>0xa000);
 167                                         bits<<=1;
 168                                         bits|=(buf[i]>0xa000);
 169                                         c++;
 170                                         if(c>=33){
 171 #if 0
 172                                                 struct timeval now;
 173
 174                                                 gettimeofday(&now,NULL);
 175                                                 printf(" %08x %ld.%06ld\n",bits,now.tv_sec,now.tv_usec);
 176                                                 c=0;
 177                                                 bits=0;
 178 #else
 179                                                 printf(" %08x\n",bits);
 180                                                 c=0;
 181                                                 bits=0;
 182 #endif
 183                                         }
 184                                         if(!bits)c=0;
 185 #endif
 186                                 }
 187                                 fflush(stdout);
 188                                 fflush(stderr);
 189                         }
 190                 }
 191         }
 192 }
 193
 194 unsigned int chanlist[16];
 195 /*
 196  * This part of the demo measures channels 1, 2, 3, 4 at a rate of
 197  * 10 khz, with the inter-sample time at 10 us (100 khz).  The number
 198  * of scans measured is 10.  This is analogous to the old mode2
 199  * acquisition.
 200  */
 201 void prepare_cmd(comedi_t *dev,comedi_cmd *cmd)
 202 {
 203         memset(cmd,0,sizeof(comedi_cmd));
 204
 205         /* the subdevice that the command is sent to */
 206         cmd->subdev =           subdevice;
 207
 208         /* flags */
 209         cmd->flags =            TRIG_WAKE_EOS;
 210
 211         cmd->start_src =        TRIG_NOW;
 212         cmd->start_arg =        0;
 213
 214         cmd->scan_begin_src =   TRIG_EXT;
 215         cmd->scan_begin_arg =   CR_EDGE | CR_INVERT | pin_clk;
 216
 217 #if 1
 218         cmd->convert_src =      TRIG_TIMER;
 219         cmd->convert_arg =      1;
 220 #else
 221         cmd->convert_src =      TRIG_ANY;
 222         cmd->convert_arg =      0;
 223 #endif
 224
 225         cmd->scan_end_src =     TRIG_COUNT;
 226         cmd->scan_end_arg =     1;
 227
 228         cmd->stop_src =         TRIG_NONE;
 229         cmd->stop_arg =         0;
 230
 231         cmd->chanlist =         chanlist;
 232         cmd->chanlist_len =     1;
 233
 234         chanlist[0]=CR_PACK(pin_data,0,0);
 235 }
 236