Files

142 lines
6.0 KiB
C

/*
* FreeModbus Libary: A portable Modbus implementation for Modbus ASCII/RTU.
* Copyright (c) 2016, 2017 Nucleron R&D LLC <main@nucleron.ru>
* Copyright (C) 2013 Armink <armink.ztl@gmail.com>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* File: $Id: mbfuncdisc_m.c, v 1.60 2013/10/15 8:48:20 Armink Add Master Functions Exp $
*/
#include "mb_common.h"
#include "mb_proto.h"
#include "transport_common.h"
#include "mb_master.h"
/* ----------------------- Defines ------------------------------------------*/
#define MB_PDU_REQ_READ_ADDR_OFF (MB_PDU_DATA_OFF + 0)
#define MB_PDU_REQ_READ_DISCCNT_OFF (MB_PDU_DATA_OFF + 2)
#define MB_PDU_REQ_READ_SIZE (4)
#define MB_PDU_FUNC_READ_DISCCNT_OFF (MB_PDU_DATA_OFF + 0)
#define MB_PDU_FUNC_READ_VALUES_OFF (MB_PDU_DATA_OFF + 1)
#define MB_PDU_FUNC_READ_SIZE_MIN (1)
/* ----------------------- Static functions ---------------------------------*/
mb_exception_t mb_error_to_exception(mb_err_enum_t error_code);
/* ----------------------- Start implementation -----------------------------*/
#if MB_MASTER_RTU_ENABLED || MB_MASTER_ASCII_ENABLED || MB_MASTER_TCP_ENABLED
#if MB_FUNC_READ_DISCRETE_INPUTS_ENABLED
/**
* This function will request read discrete inputs.
*
* @param snd_addr salve address
* @param discrete_addr discrete start address
* @param discrete_num discrete total number
* @param timeout timeout (-1 will waiting forever)
*
* @return error code
*/
mb_err_enum_t mbm_rq_read_discrete_inputs(mb_base_t *inst, uint8_t snd_addr, uint16_t discrete_addr, uint16_t discrete_num, uint32_t tout)
{
uint8_t *mb_frame_ptr;
if (!inst || (snd_addr > MB_ADDRESS_MAX)) {
return MB_EINVAL;
}
if (!mb_port_event_res_take(inst->port_obj, tout)) {
return MB_EBUSY;
}
inst->get_send_buf(inst, &mb_frame_ptr);
inst->set_dest_addr(inst, snd_addr);
mb_frame_ptr[MB_PDU_FUNC_OFF] = MB_FUNC_READ_DISCRETE_INPUTS;
mb_frame_ptr[MB_PDU_REQ_READ_ADDR_OFF] = discrete_addr >> 8;
mb_frame_ptr[MB_PDU_REQ_READ_ADDR_OFF + 1] = discrete_addr;
mb_frame_ptr[MB_PDU_REQ_READ_DISCCNT_OFF ] = discrete_num >> 8;
mb_frame_ptr[MB_PDU_REQ_READ_DISCCNT_OFF + 1] = discrete_num;
inst->set_send_len(inst, MB_PDU_SIZE_MIN + MB_PDU_REQ_READ_SIZE);
(void)mb_port_event_post(inst->port_obj, EVENT(EV_FRAME_TRANSMIT | EV_TRANS_START) );
return mb_port_event_wait_req_finish(inst->port_obj);
}
mb_exception_t mbm_fn_read_discrete_inputs(mb_base_t *inst, uint8_t *frame_ptr, uint16_t *len_buf)
{
uint8_t byte_num;
uint8_t *mb_frame_ptr;
uint16_t discrete_cnt;
uint16_t reg_address;
mb_exception_t status = MB_EX_NONE;
mb_err_enum_t reg_status = MB_EILLFUNC;
if (inst->transp_obj->frm_is_bcast(inst->transp_obj)) {
status = MB_EX_NONE;
} else if (*len_buf >= MB_PDU_SIZE_MIN + MB_PDU_FUNC_READ_SIZE_MIN) {
inst->get_send_buf(inst, &mb_frame_ptr);
reg_address = (uint16_t)(mb_frame_ptr[MB_PDU_REQ_READ_ADDR_OFF] << 8);
reg_address |= (uint16_t)(mb_frame_ptr[MB_PDU_REQ_READ_ADDR_OFF + 1]);
reg_address++;
discrete_cnt = (uint16_t)(mb_frame_ptr[MB_PDU_REQ_READ_DISCCNT_OFF] << 8);
discrete_cnt |= (uint16_t)(mb_frame_ptr[MB_PDU_REQ_READ_DISCCNT_OFF + 1]);
/* Test if the quantity of coils is a multiple of 8. If not last
* byte is only partially field with unused coils set to zero. */
if ((discrete_cnt & 0x0007) != 0) {
byte_num = (uint8_t)(discrete_cnt / 8 + 1);
} else {
byte_num = (uint8_t)(discrete_cnt / 8);
}
/* Check if the number of registers to read is valid. If not
* return Modbus illegal data value exception.
*/
if ((discrete_cnt >= 1) && byte_num == frame_ptr[MB_PDU_FUNC_READ_DISCCNT_OFF]) {
/* Make callback to fill the buffer. */
if (inst->rw_cbs.reg_discrete_cb) {
reg_status = inst->rw_cbs.reg_discrete_cb(inst, &frame_ptr[MB_PDU_FUNC_READ_VALUES_OFF],
reg_address, discrete_cnt);
}
/* If an error occured convert it into a Modbus exception. */
if(reg_status != MB_ENOERR) {
status = mb_error_to_exception(reg_status);
}
} else {
status = MB_EX_ILLEGAL_DATA_VALUE;
}
} else {
/* Can't be a valid read coil register request because the length
* is incorrect. */
status = MB_EX_ILLEGAL_DATA_VALUE;
}
return status;
}
#endif
#endif // #if MB_SERIAL_MASTER_RTU_ENABLED || MB_SERIAL_MASTER_ASCII_ENABLED || MB_MASTER_TCP_ENABLED