wip

serialtimetest/serialtimetest.c

@@ -19,9 +19,11 @@
 #include <stdlib.h>
 //
 int speed,port;
+float delay;
 unsigned char msg0 = 0;
 unsigned char msg1 = 255;
-unsigned char buf[4] = {0,100,200,255};
+//unsigned char buf[4] = {0,100,200,255};
+unsigned char buf[1] = {200};
 //
 void timer_handler (int signum) {
    write(port,&buf,4);
@@ -39,11 +41,14 @@ void timer_handler (int signum) {
    }
 //
 int main(int argc,char *argv[]) {
-   if (argc != 3) {
-      printf("command line: serialtimetest port speed\n");
+   if (argc != 4) {
+      printf("command line: serialtimetest port speed delay\n");
       return -1;
       }
    //
+   // set up port
+   //
+   delay = atof(argv[3]);
    speed = atoi(argv[2]);
    port = open(argv[1],O_RDWR|O_NOCTTY|O_NDELAY);
    fcntl(port,F_SETFL,0);
@@ -61,16 +66,35 @@ int main(int argc,char *argv[]) {
    cfsetospeed(&term,speed);
    tcsetattr(port,TCSANOW,&term);
    //
+   // alarm version
+   //
    struct sigaction sa;
    struct itimerval timer;
    memset (&sa, 0, sizeof (sa));
    sa.sa_handler = &timer_handler;
    sigaction (SIGALRM, &sa, NULL);
    timer.it_value.tv_sec = 0;
-   timer.it_value.tv_usec = 100;
+   timer.it_value.tv_usec = delay*1.0e6;
    timer.it_interval.tv_sec = 0;
-   timer.it_interval.tv_usec = 100;
+   timer.it_interval.tv_usec = delay*1.0e6;
    setitimer (ITIMER_REAL,&timer,NULL);
-   //
    while (1);
+   /*
+   //
+   // loop version
+   //
+   struct timeval time;
+   double newtime,oldtime;
+   gettimeofday(&time,NULL);
+   oldtime = time.tv_sec+time.tv_usec/1.0e6;
+   while (1) {
+      gettimeofday(&time,NULL);
+      newtime = time.tv_sec+time.tv_usec/1.0e6;
+      if ((newtime-oldtime) >= delay) {
+         oldtime = newtime;
+         //write(port,&buf,4);
+         write(port,&buf,1);
+         }
+      }
+   */
    }

serialtimetest/serialtimetest.py

@@ -10,16 +10,36 @@
 # warranty is provided, and users accept all liability.
 #
 import serial,sys,time,signal
-if (len(sys.argv) != 3):
-   print("command line: serialtest.py port speed")
+if (len(sys.argv) != 4):
+   print("command line: serialtest.py port speed delay")
    sys.exit()
 device = sys.argv[1]
 baud = int(sys.argv[2])
-print('open '+device+' at ',baud)
+delay = float(sys.argv[3])
+print('open '+device+' at '+str(baud)+' delay '+str(delay))
 port = serial.Serial(device,baudrate=baud,timeout=0)
 msg0 = b"\x00"
 msg1 = b"\xff"
 flag = 0
+'''
+#
+# loop version
+#
+oldtime = time.time()
+while (1):
+   newtime = time.time()
+   if ((newtime-oldtime) >= delay):
+      oldtime = newtime
+      if (flag == 0):
+         port.write(msg0)
+         flag = 1
+      else:
+         port.write(msg1)
+         flag = 0
+'''
+#
+# alarm version
+#
 def handler(signum,stack):
    global flag
    if (flag == 0):
@@ -29,6 +49,6 @@ def handler(signum,stack):
       port.write(msg1)
       flag = 0
 signal.signal(signal.SIGALRM,handler)
-signal.setitimer(signal.ITIMER_REAL,1,0.0002)
+signal.setitimer(signal.ITIMER_REAL,1,delay)
 while (1):
    0