You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
56 lines
1.2 KiB
56 lines
1.2 KiB
/*
|
|
* modbus_rtu.c
|
|
*
|
|
* Change Logs:
|
|
* Date Author Notes
|
|
* 2024-04-01 qiyongzhong first version
|
|
*/
|
|
|
|
#include "modbus_rtu.h"
|
|
#include "modbus_crc.h"
|
|
#include "modbus_cvt.h"
|
|
|
|
#ifdef MB_USING_RTU_PROTOCOL
|
|
|
|
int mb_rtu_frm_make(u8 *buf, const mb_rtu_frm_t *frm, mb_pdu_type_t type)//生成rtu帧, 返回帧长度
|
|
{
|
|
u8 *p = buf;
|
|
p += mb_cvt_u8_put(p, frm->saddr);
|
|
p += mb_pdu_make(p, &(frm->pdu), type);
|
|
u16 crc = mb_crc_cal(buf, (int)(p - buf));
|
|
*p++ = crc;
|
|
*p++ = (crc >> 8);
|
|
return((int)(p - buf));
|
|
}
|
|
|
|
int mb_rtu_frm_parse(const u8 *buf, int len, mb_rtu_frm_t *frm, mb_pdu_type_t type)//解析rtu帧, 返回pdu数据长度, 解析失败返回0, 功能码不支持返回-1
|
|
{
|
|
if (len < MB_RTU_FRM_MIN)
|
|
{
|
|
return(0);
|
|
}
|
|
|
|
frm->saddr = *buf;
|
|
int remain = len - (MB_RTU_SADDR_SIZE + MB_RTU_CRC_SIZE);
|
|
int pdu_len = mb_pdu_parse(buf + 1, remain, &(frm->pdu), type);
|
|
if (pdu_len <= 0)
|
|
{
|
|
return(pdu_len);
|
|
}
|
|
|
|
if (remain < pdu_len)
|
|
{
|
|
return(0);
|
|
}
|
|
|
|
int flen = pdu_len + (MB_RTU_SADDR_SIZE + MB_RTU_CRC_SIZE);
|
|
u16 cal_crc = mb_crc_cal(buf, flen);
|
|
if (cal_crc != 0)
|
|
{
|
|
return(0);
|
|
}
|
|
|
|
return(pdu_len);
|
|
}
|
|
|
|
#endif
|
|
|