1 files changed, 163 insertions, 0 deletions
diff --git a/meta-facebook/meta-wedge/recipes-wedge/rackmon/rackmon/modbuscmd.c b/meta-facebook/meta-wedge/recipes-wedge/rackmon/rackmon/modbuscmd.c
new file mode 100644
index 0000000..2d33039
--- /dev/null
+++ b/meta-facebook/meta-wedge/recipes-wedge/rackmon/rackmon/modbuscmd.c
@@ -0,0 +1,163 @@
+/*
+ * Copyright 2014-present Facebook. All Rights Reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include <termios.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <stdlib.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <string.h>
+#include <errno.h>
+#include <sys/ioctl.h>
+#include <getopt.h>
+#include "modbus.h"
+
+int verbose;
+
+void usage() {
+  fprintf(stderr,
+      "modbuscmd [-v] [-t <tty>] [-g <gpio>] modbus_command\n"
+      "\ttty defaults to %s\n"
+      "\tgpio defaults to %d\n"
+      "\tmodbus command should be specified in hex\n"
+      "\teg:\ta40300000008\n",
+      DEFAULT_TTY, DEFAULT_GPIO);
+  exit(1);
+}
+
+int main(int argc, char **argv) {
+    int error = 0;
+    int fd;
+    struct termios tio;
+    char gpio_filename[255];
+    int gpio_fd = 0;
+    int gpio_n = DEFAULT_GPIO;
+    char *tty = DEFAULT_TTY;
+    char *modbus_cmd = NULL;
+    size_t cmd_len = 0;
+    verbose = 0;
+
+    int opt;
+    while((opt = getopt(argc, argv, "t:g:v")) != -1) {
+      switch (opt) {
+      case 't':
+        tty = optarg;
+        break;
+      case 'g':
+        gpio_n = atoi(optarg);
+        break;
+      case 'v':
+        verbose = 1;
+        break;
+      default:
+        usage();
+        break;
+      }
+    }
+    if(optind < argc) {
+      modbus_cmd = argv[optind];
+    }
+    if(modbus_cmd == NULL) {
+      usage();
+    }
+
+    if (verbose)
+      fprintf(stderr, "[*] Opening TTY\n");
+    fd = open(tty, O_RDWR | O_NOCTTY);
+    CHECK(fd);
+
+    if (verbose)
+      fprintf(stderr, "[*] Opening GPIO %d\n", gpio_n);
+    snprintf(gpio_filename, 255, "/sys/class/gpio/gpio%d/value", gpio_n);
+    gpio_fd = open(gpio_filename, O_WRONLY | O_SYNC);
+    CHECK(gpio_fd);
+
+    if (verbose)
+      fprintf(stderr, "[*] Setting TTY flags!\n");
+    memset(&tio, 0, sizeof(tio));
+    cfsetspeed(&tio,B19200);
+    tio.c_cflag |= PARENB;
+    tio.c_cflag |= CLOCAL;
+    tio.c_cflag |= CS8;
+    tio.c_iflag |= INPCK;
+    tio.c_cc[VMIN] = 1;
+    tio.c_cc[VTIME] = 0;
+    CHECK(tcsetattr(fd,TCSANOW,&tio));
+
+    //convert hex to bytes
+    cmd_len = strlen(modbus_cmd);
+    if(cmd_len < 4) {
+      fprintf(stderr, "Modbus command too short!\n");
+      exit(1);
+    }
+    decode_hex_in_place(modbus_cmd, &cmd_len);
+    append_modbus_crc16(modbus_cmd, &cmd_len);
+    // print command as sent
+    if (verbose)  {
+      fprintf(stderr, "Will send:  ");
+      print_hex(stderr, modbus_cmd, cmd_len);
+      fprintf(stderr, "\n");
+    }
+
+    if (verbose)
+      fprintf(stderr, "[*] Writing!\n");
+
+    // gpio on, write, wait, gpio off
+    gpio_on(gpio_fd);
+    write(fd, modbus_cmd, cmd_len);
+    waitfd(fd);
+    gpio_off(gpio_fd);
+
+    // Enable UART read
+    tio.c_cflag |= CREAD;
+    CHECK(tcsetattr(fd,TCSANOW,&tio));
+
+    if(verbose)
+      fprintf(stderr, "[*] reading any response...\n");
+    // Read back response
+    char modbus_buf[255];
+    size_t mb_pos = 0;
+    memset(modbus_buf, 0, sizeof(modbus_buf));
+    mb_pos = read_wait(fd, modbus_buf, sizeof(modbus_buf), 90000);
+    if(mb_pos >= 4) {
+      uint16_t crc = modbus_crc16(modbus_buf, mb_pos - 2);
+      if(verbose)
+        fprintf(stderr, "Modbus response CRC: %04X\n ", crc);
+      if((modbus_buf[mb_pos - 2] == (crc >> 8)) &&
+          (modbus_buf[mb_pos - 1] == (crc & 0x00FF))) {
+        if(verbose)
+          fprintf(stderr, "CRC OK!\n");
+        print_hex(stdout, modbus_buf, mb_pos);
+        printf("\n");
+      } else {
+        fprintf(stderr, "BAD CRC :(\n");
+        return 5;
+      }
+    } else {
+      fprintf(stderr, "No response :(\n");
+      return 4;
+    }
+
+cleanup:
+    if(error != 0) {
+      error = 1;
+      fprintf(stderr, "%s\n", strerror(errno));
+    }
+    return error;
+}