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AirConditioner.c
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| #include <stdio.h> | |
| #include <unistd.h> | |
| #include <string.h> | |
| #include <stdlib.h> | |
| #include <errno.h> | |
| #include <modbus.h> | |
| const int START_REG = 36; | |
| int main(int argc, char *argv[]) | |
| { | |
| modbus_t *ctx = NULL; | |
| uint16_t tab_reg[64]; | |
| int rc; | |
| int i; | |
| uint8_t dest; | |
| ctx = modbus_new_rtu("/dev/ttyUSB0", 9600, 'N', 8, 1); | |
| if (ctx == NULL) { | |
| fprintf(stderr, "Unable to create the libmodbus context\n"); | |
| return -1; | |
| } | |
| modbus_set_slave(ctx, 1); | |
| if (modbus_connect(ctx) == -1) { | |
| fprintf(stderr, "Connection failed: %s\n", modbus_strerror(errno)); | |
| modbus_free(ctx); | |
| return -1; | |
| } | |
| rc = modbus_read_registers(ctx, START_REG, 2, tab_reg); | |
| if (rc == -1) { | |
| fprintf(stderr, "%s\n", modbus_strerror(errno)); | |
| return -1; | |
| } | |
| for (i=0; i < rc; i++) { | |
| printf("reg[%d]=%d (0x%X)\n", i+START_REG, tab_reg[i], tab_reg[i]); | |
| } | |
| modbus_close(ctx); | |
| modbus_free(ctx); | |
| } |
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