Component: Modbus Slave (SCADA) (Comms: System)

Author	Matrix TSL
Version	1.0
Category	Comms: System

Modbus Slave (SCADA) component

Modbus component for creating Modbus compatible slave hardware via RS232 or RS485.

Component Pack

SCADA

Detailed description

No detailed description exists yet for this component

Examples

No additional examples

Downloadable macro reference

	ReadHoldingRegister
Reads the value of a single holding register.
- UINT	Address
Coil Address
- UINT	Return

	SetCoil
Sets the state of a single digital coil.
- UINT	Address
Coil Address
- BYTE	State
0=off, 1=on
- VOID	Return

	SetDigitalInput
Sets the state of a single digital input.
- UINT	Address
Coil Address
- BYTE	State
0=off, 1=on
- VOID	Return

	SetSlaveAddress
Allows the slave address to be overridden from the default slave address specified in the component property. The number of bytes used for the address is fixed by the Slave ID Bytes property to save on RAM usage.
- UINT	SlaveAddress
- VOID	Return

	ChangeFrameType
Default frame type is the type set in the component properties.
- BYTE	Type
0 = Modbus RTU / 1 = Modbus ASCII
- VOID	Return

	ReadCoils
Reads the state of up to eight digital coils. Can pack a max of 8-bits together in a single operation
- UINT	StartAddress
Coil Address Range 0 to (NumCoils - 1)
- BYTE	AddressCount
Range 1-8
- BYTE	Return

	SetHoldingRegister
Sets the state of a single holding register.
- UINT	Address
Coil Address
- UINT	Value
Analogue Value range 0 - 65535
- VOID	Return

	ReadAnalogInput
Reads the value of a single analogue input.
- UINT	Address
Coil Address
- UINT	Return

	CheckForIncoming
Checks for an incoming message and if the data address is within range then also automatically replies with the correct reply. Returns 0 if no comms received, 1 for a succesful transaction, 255 for an error.
- BYTE	Return

	ReadDigitalInputs
Reads the state of up to eight digital inputs. Can pack a max of 8-bits together in a single operation
- UINT	StartAddress
Coil Address Range 0 to (NumCoils - 1)
- BYTE	AddressCount
Range 1-8
- BYTE	Return

	GetLastIncoming
Gets a value from the last incoming command. Index 0 = 0 Read / 1 Write Index 1 = 0 Coils / 1 DigInput / 2 AnInput / 3 Register Index 2 = Address Index 3 = Number
- UINT	Return

	SetAnalogInput
Sets the state of a single analogue input.
- UINT	Address
Coil Address
- UINT	Value
Analogue Value range 0 - 65535
- VOID	Return

	Initialise
Starts up the UART to allow communications and initialises the states of the various Modbus Coils, Inputs and Registers to 0.
- VOID	Return

Property reference

	Properties
	Modbus Properties
	Frame Type
Switches between RTU and ASCII forms of Modbus
	Receive Buffer Size
Maximum number of bytes the receive buffer can hold
	Receive Timeout
Length in milliseconds to wait for additional bytes to be received when checking for incoming messages.
	Slave ID Bytes
Number of bytes used when passing a slave ID, usually 1 but sometimes 2
	Slave Address
	Reply Delay
Delay in micro seconds to wait before transmitting a reply
	Maintain Stats
Controls if the last command from the master is logged allowing for easier value updates. No - Do not log commands Yes - Commands are logged and available via the GetLastIncoming macro
	Runtime Properties
	Label
A text label to appear on the Modbus panel object.
	Console Data
Selects if the console data is automatically generated or not
	Console Columns
Number of characters that can be displayed on a single line of the console.
	Data Source
Simulation data source used to allow the component to connect to various remote devices Nothing - Simulation data is ignored COM port - Routes the communication data to and from a physical or virtual COM port Injector - Routes the communication data via a data injector component on the Panel.
	COM Port
Lists all the current available COM port hardware on your PC.
	Refresh Ports
	Baud Rate
COM port data rate in bits per second
	Modbus Coils - Single bit values
	Starting Address
Start address of the Modbus coils. Referenced from 0. For example Slave 1 might have 100 coils addressed 0-99 Start Address = 0 Slave 2 might have 100 coils addressed 100-199 Start Address = 100
	Number of Addresses
Specifies how many Coils are available on the slave. Each address consumes a single bit of RAM, 8 Addresses are packed together into a single RAM Byte.
	Digital Inputs - Single bit values
	Starting Address
Start address of the Modbus digital inputs. Referenced from 0. For example Slave 1 might have 100 inputs addressed 0-99 Start Address = 0 Slave 2 might have 100 inputs addressed 100-199 Start Address = 100
	Number of Addresses
Specifies how many Digital Inputs are available on the slave. Each address consumes a single bit of RAM, 8 Addresses are packed together into a single RAM Byte.
	Analog Inputs - 16-bit values
	Starting Address
Start address of the Modbus analogue inputs. Referenced from 0. For example Slave 1 might have 100 inputs addressed 0-99 Start Address = 0 Slave 2 might have 100 inputs addressed 100-199 Start Address = 100
	Number of Addresses
Specifies how many 16-bit analogue inputs are available on the slave. Each address consumes two RAM Bytes.
	Holding Registers - 16-bit values
	Starting Address
Start address of the Modbus registers. Referenced from 0. For example Slave 1 might have 100 registers addressed 0-99 Start Address = 0 Slave 2 might have 100 registers addressed 100-199 Start Address = 100
	Number of Addresses
Specifies how many 16-bit holding registers are available on the slave. Each address consumes two RAM Bytes.