modbus_serial.h File Reference

Modbus serial defnitions and functions. More...

#include <stdbool.h>
#include <modbus_core/modbus.h>
#include <modbus_core/modbus_exceptions.h>
#include <modbus_core/modbus_types.h>
#include <modbus_core/modbus_rtos.h>

Data Structures
struct	mb_ser_adu_t
	This structure represents a serial line modbus ADU. More...
struct	timer_t
struct	mb_ser_channel_t
	This structure represents the configuration of a modbus channel. More...

Macros
#define	MB_SER_MODE_ASCII   (0)
	Modbus serial ASCII mode.
#define	MB_SER_MODE_RTU   (1)
	Modbus serial RTU mode.

Functions
void	mb_start_tx (mb_ser_channel_t *ch, mb_ser_adu_t *msg)
	Sends the given message on the given channel.
bool	mb_is_rx_msg (mb_ser_channel_t *ch)
	Checks if there is a message in the receiving queue for the given channel.
mb_ser_channel_t *	mb_serial_open (uintptr_t task_no, uint8_t mb_ser_mode, uint8_t jbus, uint8_t baud, uint8_t frame, uint8_t port, uint8_t timer, mb_data_handlers_t *handlers, uint8_t address, uint16_t timeout)
	Opens a modbus serial channel.
void	mb_serial_close (mb_ser_channel_t *ch)
	Closes e modbus channel.
void	mb_serial_set_timeout (mb_ser_channel_t *ch, uint16_t timeout)
	Sets the timeout of the specified modbus channel.
uint16_t	mb_slave_loop (mb_ser_channel_t *ch, uint32_t timeout)
	Handles the Modbus slave protocol stack.
int	mb_ser_rd_coils (mb_ser_channel_t *ch, uint8_t *buf, uint8_t addr, uint16_t start_addr, uint16_t qty, uint16_t timeout)
	Read Coils.
int	mb_ser_rd_discrete_inputs (mb_ser_channel_t *ch, uint8_t *buf, uint8_t addr, uint16_t start_addr, uint16_t qty, uint16_t timeout)
	Read Discrete Inputs.
int	mb_ser_rd_holding_regs (mb_ser_channel_t *ch, uint16_t *buf, uint8_t addr, uint16_t start_addr, uint16_t qty, uint16_t timeout)
	Read Holding Registers.
int	mb_ser_rd_input_regs (mb_ser_channel_t *ch, uint16_t *buf, uint8_t addr, uint16_t start_addr, uint16_t qty, uint16_t timeout)
	Read Input Registers.
int	mb_ser_wr_single_coil (mb_ser_channel_t *ch, bool value, uint8_t addr, uint16_t output_addr, uint16_t timeout)
	Write Single Coil.
int	mb_ser_wr_single_reg (mb_ser_channel_t *ch, uint16_t value, uint8_t addr, uint16_t output_addr, uint16_t timeout)
	Write Single Register.
int	mb_ser_wr_coils (mb_ser_channel_t *ch, uint8_t *values, uint8_t addr, uint16_t start_addr, uint16_t qty, uint16_t timeout)
	Write Multiple Coils.
int	mb_ser_wr_regs (mb_ser_channel_t *ch, uint16_t *values, uint8_t addr, uint16_t start_addr, uint16_t qty, uint16_t timeout)
	Write Multiple Registers.

Detailed Description

Modbus serial defnitions and functions.

Author

Tecnologix, 2014

Function Documentation

mb_is_rx_msg()

bool mb_is_rx_msg

(

mb_ser_channel_t *

ch

)

Checks if there is a message in the receiving queue for the given channel.

Parameters

ch	pointer to the channel to check.

Returns

true if a message was received, false otherwise.

mb_ser_rd_coils()

int mb_ser_rd_coils	(	mb_ser_channel_t *	ch,
		uint8_t *	buf,
		uint8_t	addr,
		uint16_t	start_addr,
		uint16_t	qty,
		uint16_t	timeout )

Read Coils.

Parameters

ch	modbus channel.
buf	buffer where to store read values.
addr	slave address.
start_addr	starting address of coils to read.
qty	number of coils to read.
timeout	maximum time to wait for the response.

Returns

MB_RC_OK data were read without errors, an error code otherwise.

mb_ser_rd_discrete_inputs()

int mb_ser_rd_discrete_inputs	(	mb_ser_channel_t *	ch,
		uint8_t *	buf,
		uint8_t	addr,
		uint16_t	start_addr,
		uint16_t	qty,
		uint16_t	timeout )

Read Discrete Inputs.

Parameters

ch	modbus channel.
buf	buffer where to store read values.
addr	slave address.
start_addr	starting address of discrete inputs to read.
qty	number of discrete inputs to read.
timeout	maximum time to wait for the response.

Returns

MB_RC_OK data were read without errors, an error code otherwise.

mb_ser_rd_holding_regs()

int mb_ser_rd_holding_regs	(	mb_ser_channel_t *	ch,
		uint16_t *	buf,
		uint8_t	addr,
		uint16_t	start_addr,
		uint16_t	qty,
		uint16_t	timeout )

Read Holding Registers.

Parameters

ch	modbus channel.
buf	buffer where to store read values.
addr	slave address.
start_addr	starting address of holding registers to read.
qty	number of holding registers to read.
timeout	maximum time to wait for the response.

Returns

MB_RC_OK data were read without errors, an error code otherwise.

mb_ser_rd_input_regs()

int mb_ser_rd_input_regs	(	mb_ser_channel_t *	ch,
		uint16_t *	buf,
		uint8_t	addr,
		uint16_t	start_addr,
		uint16_t	qty,
		uint16_t	timeout )

Read Input Registers.

Parameters

ch	modbus channel.
buf	buffer where to store read values.
addr	slave address.
start_addr	starting address of input registers to read.
qty	number of input registers to read.
timeout	maximum time to wait for the response.

Returns

MB_RC_OK data were read without errors, an error code otherwise.

mb_ser_wr_coils()

int mb_ser_wr_coils	(	mb_ser_channel_t *	ch,
		uint8_t *	values,
		uint8_t	addr,
		uint16_t	start_addr,
		uint16_t	qty,
		uint16_t	timeout )

Write Multiple Coils.

Parameters

ch	modbus channel.
values	values of the coils to set.
addr	slave address.
start_addr	starting address of the coils to write.
qty	number of coils to write.
timeout	maximum time to wait for the response.

Returns

MB_RC_OK data were written without errors, an error code otherwise.

mb_ser_wr_regs()

int mb_ser_wr_regs	(	mb_ser_channel_t *	ch,
		uint16_t *	values,
		uint8_t	addr,
		uint16_t	start_addr,
		uint16_t	qty,
		uint16_t	timeout )

Write Multiple Registers.

Parameters

ch	modbus channel.
values	values of the registers to set.
addr	slave address.
start_addr	starting address of the registers to write.
qty	number of registers to write.
timeout	maximum time to wait for the response.

Returns

MB_RC_OK data were written without errors, an error code otherwise.

mb_ser_wr_single_coil()

int mb_ser_wr_single_coil	(	mb_ser_channel_t *	ch,
		bool	value,
		uint8_t	addr,
		uint16_t	output_addr,
		uint16_t	timeout )

Write Single Coil.

Parameters

ch	modbus channel.
value	value of the coil to set.
addr	slave address.
output_addr	address of the coil to write.
timeout	maximum time to wait for the response.

Returns

MB_RC_OK data were written without errors, an error code otherwise.

mb_ser_wr_single_reg()

int mb_ser_wr_single_reg	(	mb_ser_channel_t *	ch,
		uint16_t	value,
		uint8_t	addr,
		uint16_t	output_addr,
		uint16_t	timeout )

Write Single Register.

Parameters

ch	modbus channel.
value	value of the register to set.
addr	slave address.
output_addr	address of the register to write.
timeout	maximum time to wait for the response.

Returns

MB_RC_OK data were written without errors, an error code otherwise.

mb_serial_close()

void mb_serial_close

(

mb_ser_channel_t *

ch

)

Closes e modbus channel.

Parameters

ch	pointer to the modbus channel to close.

mb_serial_open()

mb_ser_channel_t * mb_serial_open	(	uintptr_t	task_no,
		uint8_t	mb_ser_mode,
		uint8_t	jbus,
		uint8_t	baud,
		uint8_t	frame,
		uint8_t	port,
		uint8_t	timer,
		mb_data_handlers_t *	handlers,
		uint8_t	address,
		uint16_t	timeout )

Opens a modbus serial channel.

Parameters

task_no	number of the task that processes messages, 0 if signals should not be used.
mb_ser_mode	MB_SER_MODE_ASCII or MB_SER_MODE_RTU.
jbus	whether or not this channel use jbus mode.
baud	baudrate to use.
frame	configuration of the serial port.
port	serial port to use.
timer	timer to use.
handlers	pointer to the data handlers structure containing the function pointers to use to process modbus requests.
address	address of the node, 0 if this node is a master.
timeout	timeout to set, expressed in number of time slots of 51 microsec.

Returns

a pointer to the opened channel.

mb_serial_set_timeout()

void mb_serial_set_timeout	(	mb_ser_channel_t *	ch,
		uint16_t	timeout )

Sets the timeout of the specified modbus channel.

Parameters

ch	modbus channel to set the timeout for.
timeout	timeout to set, expressed in number of time slots of 25 microsec.

mb_slave_loop()

uint16_t mb_slave_loop	(	mb_ser_channel_t *	ch,
		uint32_t	timeout )

Handles the Modbus slave protocol stack.

It should be called regularly.

Parameters

ch	modbus channel to set the timeout for.
timeout	if not set to 0, it's the maximum time to wait for a signal to wake-up the process calling this function.

Returns

MSG_RECEIVED if a message was received and processed, MSG_TIMEOUT otherwise.

mb_start_tx()

void mb_start_tx	(	mb_ser_channel_t *	ch,
		mb_ser_adu_t *	msg )

Sends the given message on the given channel.

Parameters

ch	pointer to the channel to use.
msg	message to send.