2 * This file is part of the libsigrok project.
4 * Copyright (C) 2015 Aurelien Jacobs <aurel@gnuage.org>
6 * This program is free software: you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation, either version 3 of the License, or
9 * (at your option) any later version.
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
16 * You should have received a copy of the GNU General Public License
17 * along with this program. If not, see <http://www.gnu.org/licenses/>.
24 #include <libsigrok/libsigrok.h>
25 #include "libsigrok-internal.h"
27 #define LOG_PREFIX "modbus_serial"
29 #ifdef HAVE_SERIAL_COMM
31 #define BUFFER_SIZE 1024
33 struct modbus_serial_rtu {
34 struct sr_serial_dev_inst *serial;
39 static int modbus_serial_rtu_dev_inst_new(void *priv, const char *resource,
40 char **params, const char *serialcomm, int modbusaddr)
42 struct modbus_serial_rtu *modbus = priv;
46 modbus->serial = sr_serial_dev_inst_new(resource, serialcomm);
47 modbus->slave_addr = modbusaddr;
52 static int modbus_serial_rtu_open(void *priv)
54 struct modbus_serial_rtu *modbus = priv;
55 struct sr_serial_dev_inst *serial = modbus->serial;
57 if (serial_open(serial, SERIAL_RDWR) != SR_OK)
60 if (serial_flush(serial) != SR_OK)
66 static int modbus_serial_rtu_source_add(struct sr_session *session, void *priv,
67 int events, int timeout, sr_receive_data_callback cb, void *cb_data)
69 struct modbus_serial_rtu *modbus = priv;
70 struct sr_serial_dev_inst *serial = modbus->serial;
72 return serial_source_add(session, serial, events, timeout, cb, cb_data);
75 static int modbus_serial_rtu_source_remove(struct sr_session *session,
78 struct modbus_serial_rtu *modbus = priv;
79 struct sr_serial_dev_inst *serial = modbus->serial;
81 return serial_source_remove(session, serial);
84 static uint16_t modbus_serial_rtu_crc(uint16_t crc,
85 const uint8_t *buffer, int len)
89 if (!buffer || len < 0)
94 for (i = 0; i < 8; i++) {
105 static int modbus_serial_rtu_send(void *priv,
106 const uint8_t *buffer, int buffer_size)
109 struct modbus_serial_rtu *modbus = priv;
110 struct sr_serial_dev_inst *serial = modbus->serial;
111 uint8_t slave_addr = modbus->slave_addr;
114 result = serial_write_blocking(serial, &slave_addr, sizeof(slave_addr), 0);
118 result = serial_write_blocking(serial, buffer, buffer_size, 0);
122 crc = modbus_serial_rtu_crc(0xFFFF, &slave_addr, sizeof(slave_addr));
123 crc = modbus_serial_rtu_crc(crc, buffer, buffer_size);
125 result = serial_write_blocking(serial, &crc, sizeof(crc), 0);
132 static int modbus_serial_rtu_read_begin(void *priv, uint8_t *function_code)
134 struct modbus_serial_rtu *modbus = priv;
138 ret = serial_read_blocking(modbus->serial, &slave_addr, 1, 500);
139 if (ret != 1 || slave_addr != modbus->slave_addr)
142 ret = serial_read_blocking(modbus->serial, function_code, 1, 100);
146 modbus->crc = modbus_serial_rtu_crc(0xFFFF, &slave_addr, sizeof(slave_addr));
147 modbus->crc = modbus_serial_rtu_crc(modbus->crc, function_code, 1);
152 static int modbus_serial_rtu_read_data(void *priv, uint8_t *buf, int maxlen)
154 struct modbus_serial_rtu *modbus = priv;
157 ret = serial_read_nonblocking(modbus->serial, buf, maxlen);
160 modbus->crc = modbus_serial_rtu_crc(modbus->crc, buf, ret);
164 static int modbus_serial_rtu_read_end(void *priv)
166 struct modbus_serial_rtu *modbus = priv;
170 ret = serial_read_blocking(modbus->serial, &crc, sizeof(crc), 100);
174 if (crc != modbus->crc) {
175 sr_err("CRC error (0x%04X vs 0x%04X).", crc, modbus->crc);
182 static int modbus_serial_rtu_close(void *priv)
184 struct modbus_serial_rtu *modbus = priv;
186 return serial_close(modbus->serial);
189 static void modbus_serial_rtu_free(void *priv)
191 struct modbus_serial_rtu *modbus = priv;
193 sr_serial_dev_inst_free(modbus->serial);
196 SR_PRIV const struct sr_modbus_dev_inst modbus_serial_rtu_dev = {
197 .name = "serial_rtu",
199 .priv_size = sizeof(struct modbus_serial_rtu),
201 .dev_inst_new = modbus_serial_rtu_dev_inst_new,
202 .open = modbus_serial_rtu_open,
203 .source_add = modbus_serial_rtu_source_add,
204 .source_remove = modbus_serial_rtu_source_remove,
205 .send = modbus_serial_rtu_send,
206 .read_begin = modbus_serial_rtu_read_begin,
207 .read_data = modbus_serial_rtu_read_data,
208 .read_end = modbus_serial_rtu_read_end,
209 .close = modbus_serial_rtu_close,
210 .free = modbus_serial_rtu_free,