modbus_slave.c 18 KB

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  1. #include"modbus_slave.h"
  2. #include <string.h>
  3. //数据区域表
  4. //从站数据读取域总缓冲池
  5. static modbus_dataarea_t data_area_table[MODBUS_SLAVE_DATAAREA_POOL_SIZE];
  6. static int data_area_count = 0;
  7. /**
  8. * 查找有效的数据域
  9. *
  10. * @author lxz
  11. *
  12. * @param group
  13. * @param id
  14. * @param cmd
  15. *
  16. * @return modbus_data_area_t*
  17. */
  18. static modbus_dataarea_t* modbus_slave_find_dataarea(modbus_slave_t * slave,
  19. unsigned char data_type,
  20. unsigned short address)
  21. {
  22. modbus_dataarea_t *data = slave->data_area_list;
  23. while (data != 0)
  24. {
  25. if (data->data_type == data_type)
  26. {
  27. if (data->address <= address && (data->address + data->number) > address)
  28. {
  29. return data;
  30. }
  31. }
  32. data = (modbus_dataarea_t *)data->next;
  33. }
  34. return 0;
  35. }
  36. /**
  37. * 读取线圈
  38. *
  39. * @author lxz
  40. *
  41. * @param group 组号
  42. * @param ack 响应命令缓冲
  43. * @param req 请求命令缓冲
  44. *
  45. * @return int 返回长度,小于0表示是错误码
  46. */
  47. static int modbus_slave_read_coils(modbus_slave_t * slave, unsigned char *ack, unsigned char *req)
  48. {
  49. unsigned short address = (req[2] << 8) + req[3];
  50. unsigned short number = (req[4] << 8) + req[5];
  51. char shift = 0;
  52. int len = 0;
  53. int index = 0;
  54. unsigned char *coils;
  55. //读取符合条件的数据域信息
  56. modbus_dataarea_t *data = modbus_slave_find_dataarea(slave, 0x01, address);
  57. //没有找到
  58. if (data == 0)
  59. {
  60. return -2;
  61. }
  62. //超过数量或者地址限制
  63. if (number > 0x7F8 || number == 0 || (data->address + data->number) < (number + address))
  64. {
  65. return -3;
  66. }
  67. //生成响应命令
  68. ack[2] = (number + 7) >> 3;
  69. address -= data->address;
  70. shift = address & 0x07;
  71. index = 0;
  72. len = ack[2];
  73. coils = &data->buffer[address >> 3];
  74. //如果字节对齐,可以直接拷贝
  75. if (shift == 0)
  76. {
  77. while (index < len)
  78. {
  79. ack[index + 3] = coils[index];
  80. index++;
  81. }
  82. } else
  83. {
  84. //字节不对齐需要执行移位处理
  85. unsigned char dat = 0;
  86. while (index < len)
  87. {
  88. dat = coils[index] >> shift;
  89. dat |= coils[index + 1] << (8 - shift);
  90. ack[index + 3] = dat;
  91. index++;
  92. }
  93. }
  94. return index + 3;
  95. }
  96. /**
  97. * 读取数据
  98. *
  99. * @author lxz
  100. *
  101. * @param group 组号
  102. * @param ack 响应命令缓冲
  103. * @param req 请求命令缓冲
  104. *
  105. * @return int 返回长度,小于0表示是错误码
  106. */
  107. static int modbus_slave_read_registers(modbus_slave_t * slave, unsigned char *ack, unsigned char *req)
  108. {
  109. unsigned short address = (req[2] << 8) + req[3];
  110. unsigned short number = (req[4] << 8) + req[5];
  111. int index = 0;
  112. unsigned char *reg;
  113. //读取符合条件的数据域信息
  114. modbus_dataarea_t *data = modbus_slave_find_dataarea(slave, 0x03, address);
  115. //没有找到
  116. if (data == 0)
  117. {
  118. return -2;
  119. }
  120. //超过数量或者地址限制
  121. if (number > 0x7F || number == 0 || (data->address + data->number) < (number + address))
  122. {
  123. return -3;
  124. }
  125. //生成响应命令
  126. address -= data->address;
  127. index = 0;
  128. reg = &data->buffer[address * 2];
  129. number *= 2;
  130. ack[2] = number;
  131. while (index < number)
  132. {
  133. ack[index + 3] = reg[index + 1];
  134. ack[index + 4] = reg[index];
  135. index += 2;
  136. }
  137. return index + 3;
  138. }
  139. /**
  140. * 写单个线圈
  141. *
  142. * @author lxz
  143. *
  144. * @param group 组号
  145. * @param ack 响应命令缓冲
  146. * @param req 请求命令缓冲
  147. *
  148. * @return int 返回长度,小于0表示是错误码
  149. */
  150. static int modbus_slave_write_coil(modbus_slave_t * slave, unsigned char *ack, unsigned char *req)
  151. {
  152. unsigned short address = (req[2] << 8) + req[3];
  153. unsigned short value = (req[4] << 8) + req[5];
  154. //读取符合条件的数据域信息
  155. modbus_dataarea_t *data = modbus_slave_find_dataarea(slave, 0x01, address);
  156. //没有找到
  157. if (data == 0)
  158. {
  159. return -2;
  160. }
  161. address -= data->address;
  162. if (value != 0)
  163. {
  164. data->buffer[address >> 3] |= 1 << (address & 0x07);
  165. } else
  166. {
  167. data->buffer[address >> 3] &= ~(1 << (address & 0x07));
  168. }
  169. //回调函数
  170. if (slave->on_comm != 0)
  171. {
  172. slave->on_comm(slave->id, req[1], address, 1);
  173. }
  174. //生成响应命令
  175. ack[2] = req[2];
  176. ack[3] = req[3];
  177. ack[4] = req[4];
  178. ack[5] = req[5];
  179. return 6;
  180. }
  181. /**
  182. * 写多个线圈
  183. *
  184. * @author lxz
  185. *
  186. * @param group 组号
  187. * @param ack 响应命令缓冲
  188. * @param req 请求命令缓冲
  189. *
  190. * @return int 返回长度,小于0表示是错误码
  191. */
  192. static int modbus_slave_write_coils(modbus_slave_t * slave, unsigned char *ack, unsigned char *req)
  193. {
  194. unsigned short address = (req[2] << 8) + req[3];
  195. unsigned short number = (req[4] << 8) + req[5];
  196. unsigned short number_old = number;
  197. char shift = 0;
  198. int index = 0;
  199. unsigned char *coils;
  200. //读取符合条件的数据域信息
  201. modbus_dataarea_t *data = modbus_slave_find_dataarea(slave, 0x01, address);
  202. //没有找到
  203. if (data == 0)
  204. {
  205. return -2;
  206. }
  207. //超过数量或者地址限制
  208. if (number > 0x7F8 || number == 0 || (data->address + data->number) < (number + address))
  209. {
  210. return -3;
  211. }
  212. //执行数据搬运
  213. ack[2] = (number + 7) >> 3;
  214. address -= data->address;
  215. shift = address & 0x07;
  216. address >>= 3;
  217. index = 0;
  218. coils = &data->buffer[address >> 3];
  219. if (shift == 0)
  220. {
  221. //整个字节部分可以直接处理
  222. while (number > 7)
  223. {
  224. coils[index] = req[index + 7];
  225. index++;
  226. number -= 8;
  227. }
  228. //非完整部分需要进行处理
  229. if (number != 0)
  230. {
  231. unsigned char dat = req[index + 7] & (0xFF >> (8 - number));
  232. coils[index] &= 0xFF << number;
  233. coils[index] |= dat;
  234. }
  235. } else
  236. {
  237. unsigned char dat = 0;
  238. unsigned char i = 0;
  239. //整个字节部分独立处理
  240. while (number > 7)
  241. {
  242. dat = coils[index] & (0xFF >> (8 - shift));
  243. coils[index] = dat | (req[index + 7] << shift);
  244. dat = coils[index + 1] & (0xFF << shift);
  245. coils[index + 1] = dat | (req[index + 7] >> (8 - shift));
  246. index++;
  247. number -= 8;
  248. }
  249. //最后一个字节不满,按位处理
  250. while (i < number)
  251. {
  252. if (req[index + 7] & (1 << i))
  253. {
  254. coils[index] |= 1 << shift;
  255. } else
  256. {
  257. coils[index] &= ~(1 << shift);
  258. }
  259. i++;
  260. shift++;
  261. if (shift > 7)
  262. {
  263. shift = 0;
  264. coils++;
  265. }
  266. }
  267. }
  268. //回调函数
  269. if (slave->on_comm !=0)
  270. {
  271. slave->on_comm(slave->id, req[1], address, number_old);
  272. }
  273. //生成响应命令
  274. ack[2] = req[2];
  275. ack[3] = req[3];
  276. ack[4] = req[4];
  277. ack[5] = req[5];
  278. return 6;
  279. }
  280. /**
  281. * 写单个寄存器
  282. *
  283. * @author lxz
  284. *
  285. * @param group 组号
  286. * @param ack 响应命令缓冲
  287. * @param req 请求命令缓冲
  288. *
  289. * @return int 返回长度,小于0表示是错误码
  290. */
  291. static int modbus_slave_write_register(modbus_slave_t * slave, unsigned char *ack, unsigned char *req)
  292. {
  293. unsigned short address = (req[2] << 8) + req[3];
  294. //读取符合条件的数据域信息
  295. modbus_dataarea_t *data = modbus_slave_find_dataarea(slave, 0x03, address);
  296. unsigned char *reg;
  297. //没有找到
  298. if (data == 0)
  299. {
  300. return -2;
  301. }
  302. address -= data->address;
  303. reg = &data->buffer[address * 2];
  304. reg[0] = req[5];
  305. reg[1] = req[4];
  306. //回调函数
  307. if (slave->on_comm != 0)
  308. {
  309. slave->on_comm(slave->id, req[1], address, 1);
  310. }
  311. //生成响应命令
  312. ack[2] = req[2];
  313. ack[3] = req[3];
  314. ack[4] = req[4];
  315. ack[5] = req[5];
  316. return 6;
  317. }
  318. /**
  319. * 进入bootloader
  320. *
  321. * @author lxz
  322. *
  323. * @param group 组号
  324. * @param ack 响应命令缓冲
  325. * @param req 请求命令缓冲
  326. *
  327. * @return int 返回长度,小于0表示是错误码
  328. */
  329. static int modbus_slave_exit_app(modbus_slave_t * slave, unsigned char *ack, unsigned char *req)
  330. {
  331. //读取符合条件的数据域信息
  332. modbus_dataarea_t *data = modbus_slave_find_dataarea(slave, 0xFE, 0);
  333. //没有找到
  334. if (data == 0)
  335. {
  336. return -2;
  337. }
  338. //超过数量或者地址限制
  339. //回调函数
  340. if (slave->on_comm != 0)
  341. {
  342. slave->on_comm(slave->id, req[1], 0xFFEE, 0);
  343. }
  344. //生成响应命令
  345. if (data->buffer != (void *)0)
  346. {
  347. ack[2] = req[2];
  348. ack[3] = req[3];
  349. ack[4] = req[4];
  350. ack[5] = req[5];
  351. return 6;
  352. } else
  353. {
  354. return -1;
  355. }
  356. }
  357. /**
  358. * 离开bootloader
  359. *
  360. * @author lxz
  361. *
  362. * @param group 组号
  363. * @param ack 响应命令缓冲
  364. * @param req 请求命令缓冲
  365. *
  366. * @return int 返回长度,小于0表示是错误码
  367. */
  368. static int modbus_slave_enter_app(modbus_slave_t * slave, unsigned char *ack, unsigned char *req)
  369. {
  370. //读取符合条件的数据域信息
  371. modbus_dataarea_t *data = modbus_slave_find_dataarea(slave, 0xFE, 0);
  372. //没有找到
  373. if (data == 0)
  374. {
  375. return -2;
  376. }
  377. //超过数量或者地址限制
  378. //回调函数
  379. if (slave->on_comm != 0)
  380. {
  381. slave->on_comm(slave->id, req[1], 0xFFEF, 0);
  382. }
  383. //生成响应命令
  384. if (data->buffer == 0)
  385. {
  386. ack[2] = req[2];
  387. ack[3] = req[3];
  388. ack[4] = req[4];
  389. ack[5] = req[5];
  390. return 6;
  391. } else
  392. {
  393. return -1;
  394. }
  395. }
  396. /**
  397. * 擦除用户程序
  398. *
  399. * @author lxz (2019/6/12/周三)
  400. *
  401. * @param group
  402. * @param ack
  403. * @param req
  404. *
  405. * @return int
  406. */
  407. static int modbus_slave_erase_app(modbus_slave_t * slave, unsigned char *ack, unsigned char *req)
  408. {
  409. //读取符合条件的数据域信息
  410. modbus_dataarea_t *data = modbus_slave_find_dataarea(slave, 0xFE, 0);
  411. //没有找到
  412. if (data == 0)
  413. {
  414. return -2;
  415. }
  416. //超过数量或者地址限制
  417. //回调函数
  418. if (slave->on_comm != 0)
  419. {
  420. slave->on_comm(slave->id, req[1], 0xFFEC, 0);
  421. }
  422. //生成响应命令
  423. if (data->buffer != 0)
  424. {
  425. ack[2] = 0x00;
  426. ack[3] = 0x00;
  427. ack[4] = 0xFF;
  428. ack[5] = 0x00;
  429. return 6;
  430. } else
  431. {
  432. return -1;
  433. }
  434. }
  435. /**
  436. * 接收用户程序
  437. *
  438. * @author lxz (2019/6/12/周三)
  439. *
  440. * @param group
  441. * @param ack
  442. * @param req
  443. *
  444. * @return int
  445. */
  446. static int modbus_slave_receive_app(modbus_slave_t * slave, unsigned char *ack, unsigned char *req)
  447. {
  448. unsigned short address = (req[2] << 8) + req[3];
  449. unsigned short number = (req[4] << 8) + req[5];
  450. unsigned char *reg;
  451. //读取符合条件的数据域信息
  452. modbus_dataarea_t *data = modbus_slave_find_dataarea(slave, 0xFE, 0);
  453. //没有找到
  454. if (data == 0)
  455. {
  456. return -2;
  457. }
  458. //超过数量或者地址限制
  459. if (data->buffer != (void *)0)
  460. {
  461. //超过数量或者地址限制
  462. if (number == 0 || (data->address + data->number) < (number + address))
  463. {
  464. return -3;
  465. }
  466. address -= data->address;
  467. reg = &data->buffer[address];
  468. memcpy(reg, &req[6], number);
  469. }
  470. //回调函数
  471. if (slave->on_comm != 0)
  472. {
  473. slave->on_comm(slave->id, req[1], 0xFFE0, 0);
  474. }
  475. //生成响应命令
  476. if (data->buffer != 0)
  477. {
  478. ack[2] = 0x00;
  479. ack[3] = 0x00;
  480. ack[4] = 0xFF;
  481. ack[5] = 0x00;
  482. return 6;
  483. } else
  484. {
  485. return -1;
  486. }
  487. }
  488. /**
  489. * 将app缓冲数据写入指定的位置
  490. *
  491. * @author lxz (2019/6/12/周三)
  492. *
  493. * @param group
  494. * @param ack
  495. * @param req
  496. *
  497. * @return int
  498. */
  499. static int modbus_slave_copy_to_flash(modbus_slave_t * slave, unsigned char *ack, unsigned char *req)
  500. {
  501. unsigned short number = (req[6] << 8) + req[7];
  502. unsigned char *reg;
  503. //读取符合条件的数据域信息
  504. modbus_dataarea_t *data = modbus_slave_find_dataarea(slave, 0xFE, 0);
  505. //没有找到
  506. if (data == 0)
  507. {
  508. return -2;
  509. }
  510. if (data->buffer != (void *)0)
  511. {
  512. //将写入地址与写入长度写在缓冲最后面
  513. reg = &data->buffer[number];
  514. reg[0] = req[2];
  515. reg[1] = req[3];
  516. reg[2] = req[4];
  517. reg[3] = req[5];
  518. }
  519. //回调函数,该函数会开始写入
  520. if (slave->on_comm != 0)
  521. {
  522. slave->on_comm(slave->id, req[1], 0xFFE1, number);
  523. }
  524. //生成响应命令
  525. if (data->buffer != 0)
  526. {
  527. ack[2] = req[2];
  528. ack[3] = req[3];
  529. ack[4] = req[4];
  530. ack[5] = req[5];
  531. return 6;
  532. }
  533. else
  534. {
  535. return -1;
  536. }
  537. }
  538. /**
  539. * 将后面附带的数据直接写入FLASH
  540. * 该指令用于指定直接写入
  541. *
  542. * @author lxz
  543. *
  544. * @param group
  545. * @param ack
  546. * @param req
  547. *
  548. * @return int
  549. */
  550. static int modbus_slave_write_to_flash(modbus_slave_t * slave, unsigned char *ack, unsigned char *req)
  551. {
  552. unsigned short number = (req[4] << 8) + req[5];
  553. unsigned char *reg = 0;
  554. //读取符合条件的数据域信息
  555. modbus_dataarea_t *data = modbus_slave_find_dataarea(slave, 0xFE, 0);
  556. //没有找到
  557. if (data == 0)
  558. {
  559. return -2;
  560. }
  561. if (data->buffer != (void *)0)
  562. {
  563. //将写入地址与写入长度写在缓冲最后面
  564. memcpy(data->buffer, &req[6], number);
  565. reg = &data->buffer[number];
  566. reg[0] = 0x00;
  567. reg[1] = req[2];
  568. reg[2] = req[3];
  569. reg[3] = 0x00;
  570. }
  571. //回调函数,该函数会开始写入
  572. if (slave->on_comm != 0)
  573. {
  574. slave->on_comm(slave->id, req[1], 0xFFE2, number);
  575. }
  576. //生成响应命令
  577. if (data->buffer != 0)
  578. {
  579. ack[2] = req[2];
  580. ack[3] = req[3];
  581. ack[4] = req[4];
  582. ack[5] = req[5];
  583. return 6;
  584. }
  585. else
  586. {
  587. return -1;
  588. }
  589. }
  590. /**
  591. * 写多个寄存器
  592. *
  593. * @author lxz (2019/6/12/周三)
  594. *
  595. * @param group
  596. * @param ack
  597. * @param req
  598. *
  599. * @return int
  600. */
  601. static int modbus_slave_write_registers(modbus_slave_t * slave, unsigned char *ack, unsigned char *req)
  602. {
  603. unsigned short address = (req[2] << 8) + req[3];
  604. unsigned short number = (req[4] << 8) + req[5];
  605. int index = 0;
  606. unsigned char *reg;
  607. //读取符合条件的数据域信息
  608. modbus_dataarea_t *data = modbus_slave_find_dataarea(slave, 0x03, address);
  609. //没有找到
  610. if (data == 0)
  611. {
  612. return -2;
  613. }
  614. //超过数量或者地址限制
  615. if (number > 0x7F || number == 0 || (data->address + data->number) < (number + address))
  616. {
  617. return -3;
  618. }
  619. address -= data->address;
  620. //执行数据搬运
  621. reg = &data->buffer[address * 2];
  622. number *= 2;
  623. while (index < number)
  624. {
  625. reg[index] = req[8 + index];
  626. reg[index + 1] = req[7 + index];
  627. index += 2;
  628. }
  629. //回调函数
  630. if (slave->on_comm != 0)
  631. {
  632. slave->on_comm(slave->id, req[1], address, number);
  633. }
  634. //生成响应命令
  635. ack[2] = req[2];
  636. ack[3] = req[3];
  637. ack[4] = req[4];
  638. ack[5] = req[5];
  639. return 6;
  640. }
  641. /**
  642. * 从站协议接口
  643. *
  644. * @author lxz
  645. *
  646. * @param slave 从站对象
  647. * @param ack 回应缓冲
  648. * @param req 命令缓冲
  649. *
  650. * @return int 返回需要发送的长度
  651. */
  652. int modbus_slave_run(modbus_slave_t *slave, unsigned char *ack, unsigned char *req)
  653. {
  654. int ack_len = 0;
  655. if (req[0] != slave->id) return 0;
  656. switch (req[1])
  657. {
  658. case 0x01:
  659. case 0x02:
  660. ack_len = modbus_slave_read_coils(slave, ack, req);
  661. break;
  662. case 0x03:
  663. case 0x04:
  664. ack_len = modbus_slave_read_registers(slave, ack, req);
  665. break;
  666. case 0x05:
  667. ack_len = modbus_slave_write_coil(slave, ack, req);
  668. break;
  669. case 0x06:
  670. ack_len = modbus_slave_write_register(slave, ack, req);
  671. break;
  672. case 0x0F:
  673. ack_len = modbus_slave_write_coils(slave, ack, req);
  674. break;
  675. case 0x10:
  676. ack_len = modbus_slave_write_registers(slave, ack, req);
  677. break;
  678. case 0x23:
  679. ack_len = modbus_slave_exit_app(slave, ack, req);
  680. break;
  681. case 0x24:
  682. ack_len = modbus_slave_enter_app(slave, ack, req);
  683. break;
  684. case 0x20:
  685. ack_len = modbus_slave_erase_app(slave, ack, req);
  686. break;
  687. case 0x21:
  688. ack_len = modbus_slave_receive_app(slave, ack, req);
  689. break;
  690. case 0x22:
  691. ack_len = modbus_slave_copy_to_flash(slave, ack, req);
  692. break;
  693. case 0x29:
  694. ack_len = modbus_slave_write_to_flash(slave, ack, req);
  695. break;
  696. default:
  697. ack_len = -1;
  698. break;
  699. }
  700. ack[0] = req[0];
  701. if (ack_len < 0)
  702. {
  703. ack[1] = req[1] |0x80;
  704. ack[2] = -ack_len;
  705. ack_len = 3;
  706. } else
  707. {
  708. ack[1] = req[1];
  709. }
  710. return ack_len;
  711. }
  712. /**
  713. * 向从站注册一条读取域信息
  714. *
  715. * @author lxz
  716. *
  717. * @param slave 从站对象
  718. * @param data_type
  719. * 数据类型,0x01表示位,0x03表示数值,0xFE表示系统占用
  720. * @param address 数据开始地址
  721. * @param number 数据区域长度
  722. * @param data 数据所在指针
  723. */
  724. modbus_dataarea_t * modbus_slave_add_dataarea(
  725. modbus_slave_t *slave,
  726. unsigned char data_type,
  727. unsigned short address,
  728. unsigned short number,
  729. unsigned char *data)
  730. {
  731. if (data_area_count < MODBUS_SLAVE_DATAAREA_POOL_SIZE)
  732. {
  733. modbus_dataarea_t *data_area = &data_area_table[data_area_count];
  734. modbus_dataarea_t *next = slave->data_area_list;
  735. //信息初始化
  736. data_area->data_type = data_type;
  737. data_area->address = address;
  738. data_area->number = number;
  739. data_area->buffer = data;
  740. data_area->next = 0;
  741. //插入从站对象的数据域链表中
  742. if (next == 0)
  743. {
  744. slave->data_area_list = data_area;
  745. }
  746. else
  747. {
  748. while (next->next != 0)
  749. {
  750. next = (modbus_dataarea_t *)next->next;
  751. }
  752. next->next = data_area;
  753. }
  754. //已经使用+1
  755. data_area_count++;
  756. return data_area;
  757. }
  758. return 0;
  759. }