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--- sdk:dio2modbustcp [2015/05/12 08:06]
fachet
+++ sdk:dio2modbustcp [2015/05/13 14:28]
fachet
@@ Line 1: / Line 1: @@
 ====== Access to the digital I/Os via Modbus TCP ======
-<code c dio2modbustcp.are>/* DESC: This script can be used to access to the digital I/Os via Modbus TCP
+<code c dio2modbustcp.are>
+/* DESC: This script can be used to access to the digital I/Os via Modbus TCP
  * Copyright (C) 2015 NetModule AG, Switzerland
- * supports Read Coil Status (FC01), Read Input Status (FC02) and Force Single Coil (FC05)
+ *
+ *   Commands:
+ *     Read Coil Status (FC01)
+ *     Read Input Status (FC02)
+ *     Read Input Register (FC04)
+ *     Force Single Coil (FC05)
+ *     Write Multiple Coils (FC15)
+ *
  *   Mapping:
- *     Coil(digital I/O): 1=out1, 2=out2
+ *     Coil status(digital I/O): 1=out1, 2=out2
- *     Input(digital In): 1=in1, 2=in2
+ *     Input satus(digital In): 1=in1, 2=in2
+ *     Input register : 1=temperature 2=mobile 1 rsrp
+ *
  */
 TCP_PORT    = 1502;  // sdk port must be higher than 1024
 SLAVEID     = 7;
+int set_io(int adr, int dat)
+{
+  ret = 0;
+  switch (adr) { //switch on address
+    case 0:
+      if (dat == 0)
+        nb_dio_set("out1", 0);
+      else
+        nb_dio_set("out1", 1);
+      break;
+    case 1:
+      if (dat == 0)
+        nb_dio_set("out2", 0);
+      else
+        nb_dio_set("out2", 1);
+      break;
+    default:
+    ret = -1;
+    break;
+    }
+  return ret;
+}
 if ((fd = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP)) < 0) {
-    printf("Unable to open socket\n");
+  printf("Unable to open socket\n");
-    exit(1);
+  exit(1);
 }
 if (bind(fd, TCP_PORT, "") < 0) {
-    printf("Unable to bind port %d\n", TCP_PORT);
+  printf("Unable to bind port %d\n", TCP_PORT);
-    exit(2);
+  exit(2);
 }
 if (listen(fd, 1) < 0) {
-    printf("Unable to listen\n");
+  printf("Unable to listen\n");
-    exit(3);
+  exit(3);
 }
 cfd = -1;
 for(;;) {
-    if (cfd == -1)
+  if (cfd == -1)
-    {
+  {
-        if ((cfd = accept(fd)) < 0) {
+    if ((cfd = accept(fd)) < 0) {
-            printf("accept failed\n");
+      printf("accept failed\n");
-            continue;
+      continue;
-        }
-        if (nb_modbus_register(cfd, MODBUS_TYPE_TCP) < 0) {
-            printf("Unable to register client (%s)\n", nb_modbus_last_error());
-            close(cfd);
-            cfd = -1;
-            continue;
-        }
     }
-    if ((r = nb_modbus_receive(cfd)) == NULL) {
+    if (nb_modbus_register(cfd, MODBUS_TYPE_TCP) < 0) {
-        printf("Unable to receive request (%s)\n", nb_modbus_last_error());
+      printf("Unable to register client (%s)\n", nb_modbus_last_error());
+      close(cfd);
+      cfd = -1;
+      continue;
+    }
+  }
+  if ((r = nb_modbus_receive(cfd)) == NULL) {
+    printf("Unable to receive request (%s)\n", nb_modbus_last_error());
+    nb_modbus_unregister(cfd);
+    close(cfd);
+    cfd = -1;
+    continue;
+  }
+  if (r[6] != SLAVEID)
+    continue; // not for us
+  cmd = r[7]; // command
+  switch (cmd) { // write commands
+    case 5: // write to a single coil
+      addr = r[8]<<8 + r[9];
+      data = r[10]<<8 + r[11];
+      if (set_io(addr, data) == -1)
+        continue; // error
+      break;
+    case 15: // write to multiple coils
+      addr = r[8]<<8 + r[9];
+      cnt = r[10]<<8 + r[11];
+      for (i = 0; i < cnt; i ++)
+        if (set_io(addr+i, (int) (r[13+i/8] & 1<<(i%256))) == -1)
+          continue; // error
+      break;
+  }
+  switch (cmd) { // reply for all commands
+    case 1: // read coil status
+    case 2: // read input status
+    case 5: // write to a single coil
+    case 4: // read input register
+    case 15: // write to multiple coils
+      syst = nb_status("system");
+      wwan = nb_status("wwan");
+      resp = mkstruct(
+        "bits", mkarray(nb_dio_get("out1"), nb_dio_get("out2")),
+        "ibits", mkarray(nb_dio_get("in1"), nb_dio_get("in2")),
+        "regs", mkarray(),
+        "iregs", mkarray((int)syst.TEMPERATURE, (int)wwan.MOBILE1_RSRP)
+      );
+      if (nb_modbus_reply(cfd, r, resp) < 0) {
+        printf("Unable to reply%s)\n", nb_modbus_last_error());
         nb_modbus_unregister(cfd);
         close(cfd);
         cfd = -1;
         continue;
-    }
+      }
-    if (r[6] == SLAVEID) {
+      break;
-        switch (r[7]) { // command
+  }
-            case 1: // read coil status
-            case 2: // read input status
-                break; // no write action, only reply needed
-            case 5: // write to a single coil
-                addr = r[8]<<8 + r[9];
-                data = r[10]<<8 + r[11];
-                switch (addr) { //switch on address
-                    case 0:
-                        if (data == 0)
-                            nb_dio_set("out1", 0);
-                        else
-                            nb_dio_set("out1", 1);
-                        break;
-                    case 1:
-                        if (data == 0)
-                            nb_dio_set("out2", 0);
-                        else
-                            nb_dio_set("out2", 1);
-                        break;
-                }
-                break;
-        }
-        // reply for all commands
-        resp = mkstruct(
-            "bits", mkarray(nb_dio_get("in1"), nb_dio_get("in2")),
-            "ibits", mkarray(nb_dio_get("out1"), nb_dio_get("out2")),
-            "regs", mkarray(),
-            "iregs", mkarray()
-        );
-        if (nb_modbus_reply(cfd, r, resp) < 0)
-        {
-            printf("Unable to reply%s)\n", nb_modbus_last_error());
-            nb_modbus_unregister(cfd);
-            close(cfd);
-            cfd = -1;
-            continue;
-        }
-    }
 }
 /* not reached */
 </code>

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