/*
*
* MAIN process
*
*/
int main(int argc, char* argv[])
{
char serial_port[32] = SERIAL_PORT_PREFIX;
int baud_rate;
int num_slaves;
int i, k;
if ((argc < 6) || ((argc>6) && (argc<NUM_REG_PER_SLAVE+5)))
{
printf("Usage:\n\n");
printf(" Single slave (passthrough) mode:\n");
printf(" mbrtud <serial dev> <baudrate> <num_regs> <reg_offset> <slave addr>\n");
printf(" serial dev: name of the serial device used for connection to the Modbus converter (e.g. USB0 or S0)\n");
printf(" baudrate: baudrate used for serial connection\n");
printf(" num_regs: number of consecutive registers to read\n");
printf(" reg_offset: register address offset to add for slave request\n");
printf(" slave addr: address of Modbus slave device\n\n");
printf(" Multiple slave (register mapping) mode:\n");
printf(" mbrtud <serial dev> <baudrate> <num_regs> <reg 1> ... <reg %d> <slave addr> [<slave addr> ...]\n", NUM_REG_PER_SLAVE);
printf(" serial dev: name of the serial device used for connection to the Modbus converter (e.g. USB0 or S0)\n");
printf(" baudrate: baudrate used for serial connection\n");
printf(" num_regs: number of consecutive registers to read\n");
printf(" reg x: register map to use for slave request\n");
printf(" slave addr: address of Modbus slave devices (up to %d)\n", MAX_SLAVES);
return 0;
}
openlog("mbrtud", LOG_PID|LOG_CONS, LOG_USER);
syslog(LOG_DAEMON | LOG_NOTICE, "Starting Modbus RTU daemon (version %s)\n", VERSION);
/* Install signal handler for SIGTERM and SIGINT ("CTRL C") to be used to terminate */
signal(SIGTERM, doExit);
signal(SIGINT, doExit);
/* Get input parameters */
i=1;
strcat(serial_port, argv[i++]);
baud_rate = atoi(argv[i++]);
num_regs = atoi(argv[i++]);
if (argc == 6)
{
/* Single slave (passthrough) mode */
mode=MODE_SINGLESLAVE;
reg_offset = atoi(argv[i++]);
slave_addr_table[0] = atoi(argv[i++]);
}
else
{
/* Multiple slave (register mapping) mode */
mode=MODE_MULTISLAVE;
for (k=0; (i<argc)&&(k<NUM_REG_PER_SLAVE); i++, k++)
custom_reg_table[k] = atoi(argv[i]);
memset(slave_addr_table, 0, sizeof(slave_addr_table));
for (k=0; (i<argc)&&(k<MAX_SLAVES); i++, k++)
slave_addr_table[k] = atoi(argv[i]);
num_slaves = k;
}
/* Init the Modbus RTU connection */
mb = modbus_new_rtu(serial_port, baud_rate, 'N', 8, 1);
if (mb == NULL)
{
syslog(LOG_DAEMON | LOG_ERR, "Unable to create RTU485 context\n");
modbus_free(mb);
return 1;
}
if (modbus_connect(mb) == -1)
{
syslog(LOG_DAEMON | LOG_ERR, "Connection failed: %s\n",
modbus_strerror(errno));
return 2;
}
/* Set Modbus timeouts */
modbus_set_response_timeout(mb, 20, 0);
modbus_set_byte_timeout(mb, 1, 0);
/* Specific setting for direction control of the RS485 transceiver */
if (strstr(serial_port, "USB") == NULL)
{
/* Enable RS485 direction control via RTS line */
if (modbus_rtu_set_rts(mb, MODBUS_RTU_RTS_DOWN) == -1)
{
syslog(LOG_DAEMON | LOG_ERR, "Setting RTS mode failed: %s\n",
modbus_strerror(errno));
modbus_free(mb);
return 3;
}
/* Set RTS control delay (before and after transmission) */
if (DEFAULT_RTS_DELAY > 0)
{
if (modbus_rtu_set_rts_delay(mb, DEFAULT_RTS_DELAY) == -1)
{
syslog(LOG_DAEMON | LOG_ERR, "Setting RTS delay failed: %s\n",
modbus_strerror(errno));
modbus_free(mb);
return 4;
}
}
syslog(LOG_DAEMON | LOG_NOTICE, "using direction control via RTS line");
}
//modbus_set_debug(mb, TRUE);
syslog(LOG_DAEMON | LOG_NOTICE, "Using Modbus connection on serial port %s at %dbaud",
serial_port, baud_rate);
if (mode == MODE_SINGLESLAVE)
{
syslog(LOG_DAEMON | LOG_NOTICE, "Single slave mode - slave address: %d", slave_addr_table[0]);
}
else
{
syslog(LOG_DAEMON | LOG_NOTICE, "Multiple slave mode - register map for each slave:");
syslog(LOG_DAEMON | LOG_NOTICE, " Reg | Id ");
syslog(LOG_DAEMON | LOG_NOTICE, " ---------");
for (i=0; i<NUM_REG_PER_SLAVE; i++)
syslog(LOG_DAEMON | LOG_NOTICE, " %02d | %02d", i+1, custom_reg_table[i]);
syslog(LOG_DAEMON | LOG_NOTICE, "List of slaves:");
for (i=0; i<num_slaves; i++)
syslog(LOG_DAEMON | LOG_NOTICE, " slave %d: %d (regs[%d...%d])\n",
i+1,
slave_addr_table[i],
i*NUM_REG_PER_SLAVE+1,
i*NUM_REG_PER_SLAVE+NUM_REG_PER_SLAVE);
}
/* Start Modbus TCP server loop */
modbustcp_server(MODBUS_SLAVE_ADDRESS, // Modbus slave address
read_register_handler, // Read register handler
write_register_handler // Write register handler
);
return 0;
}
int main(int argc, char *argv[])
{
modbus_t *diris;
int code;
char errmsg[255];
FILE *f_lock;
uint16_t tab_reg[64];
int i;
int debug=0;
if (argc==1)
{
fprintf(stderr,"Usage: %s <reg>\n", argv[0]);
exit(1);
}
/* Lock file */
srandom(time(NULL));
i=0;
f_lock=fopen("/var/run/modbus.lck","r");
while (i < 4 && f_lock>0)
{
fclose(f_lock);
usleep(500000*random()%10);
i++;
f_lock=fopen("/var/run/modbus.lck","r");
}
if (i==4)
{
fprintf(stderr, "Lock timeout\n");
exit(1);
}
if (f_lock<0)
{
f_lock=fopen("/var/run/modbus.lck","a");
fputs("modbus",f_lock);
fclose(f_lock);
}
/* Open Serial Device */
diris=modbus_new_rtu("/dev/ttyUSB0", 9600, 'O', 8, 1);
if (diris == NULL) {
fprintf(stderr, "Unable to create the libmodbus context\n");
unlink("/var/run/modbus.lck");
return 1;
}
/* Prepare to connect to Slave */
code=modbus_set_slave(diris, 5);
if(code <0)
{
perror(errmsg);
fprintf(stderr,"Set slave error: %s\n",errmsg);
unlink("/var/run/modbus.lck");
return 1;
}
if (debug)
modbus_set_debug(diris, 1);
if (debug)
{
/* Check Serial Mode */
code=modbus_rtu_get_serial_mode(diris);
if (code=MODBUS_RTU_RS485)
{
printf("Mode: RS485\n");
}
else
{
printf("Mode: RS232\n");
}
}
if (debug)
{
/* Check RTS Mode */
code=modbus_rtu_get_rts(diris);
switch(code)
{
case MODBUS_RTU_RTS_NONE:
printf("RTS: None\n");
break;
case MODBUS_RTU_RTS_UP:
printf("RTS: Up\n");
break;
case MODBUS_RTU_RTS_DOWN:
printf("RTS: Down\n");
break;
default:
printf("RTS: Unknown\n");
}
printf("RTS: %d\n", code);
}
/* Change RTS Mode */
modbus_rtu_set_rts(diris, MODBUS_RTU_RTS_UP);
if (debug)
{
code=modbus_rtu_get_rts(diris);
switch(code)
{
case MODBUS_RTU_RTS_NONE:
printf("RTS: None\n");
break;
case MODBUS_RTU_RTS_UP:
printf("RTS: Up\n");
break;
case MODBUS_RTU_RTS_DOWN:
printf("RTS: Down\n");
break;
default:
printf("RTS: Unknown\n");
}
printf("RTS: %d\n", code);
}
/* Initiate connect (nothing to do in serial mode) */
if (modbus_connect(diris) == -1) {
fprintf(stderr, "Connection failed: %s\n", modbus_strerror(errno));
modbus_free(diris);
unlink("/var/run/modbus.lck");
return -1;
}
if (debug) {printf("Connect OK\n");}
/* Do the read */
if (debug) { printf("Reading %s\n", argv[1]); }
/* int modbus_read_registers(modbus_t *ctx, int addr, int nb, uint16_t *dest); */
code = modbus_read_registers(diris, atoi(argv[1]), 2, tab_reg);
if (code == -1) {
fprintf(stderr, "%s\n", modbus_strerror(errno));
modbus_close(diris);
modbus_free(diris);
unlink("/var/run/modbus.lck");
return -1;
}
/* Display Value returned */
/*for (i=0; i < code; i++) {
printf("reg[%d]=%d (0x%X)\n", i, tab_reg[i], tab_reg[i]);
}
*/
if (code==2)
{
printf("%d\n", tab_reg[1]);
}
/*printf("Reset IMax\n");
code=modbus_write_register(diris, 1024, 1);
if (code == -1)
{
fprintf(stderr, "%s\n", modbus_strerror(errno));
modbus_close(diris);
modbus_free(diris);
return -1;
}*/
/* Close */
modbus_close(diris);
modbus_free(diris);
unlink("/var/run/modbus.lck");
return 0;
}
