| Safe Haskell | None |
|---|---|
| Language | Haskell2010 |
System.Modbus.TCP
Description
An implementation of the Modbus TPC/IP protocol.
This implementation is based on the MODBUS Application Protocol
Specification V1.1b
(http://www.modbus.org/docs/Modbus_Application_Protocol_V1_1b.pdf).
- data TCP_ADU = TCP_ADU {}
- data Header = Header {}
- data FunctionCode
- = ReadCoils
- | ReadDiscreteInputs
- | ReadHoldingRegisters
- | ReadInputRegisters
- | WriteSingleCoil
- | WriteSingleRegister
- | ReadExceptionStatus
- | Diagnostics
- | GetCommEventCounter
- | GetCommEventLog
- | WriteMultipleCoils
- | WriteMultipleRegisters
- | ReportSlaveID
- | ReadFileRecord
- | WriteFileRecord
- | MaskWriteRegister
- | ReadWriteMultipleRegisters
- | ReadFIFOQueue
- | EncapsulatedInterfaceTransport
- | UserDefinedCode Word8
- | ReservedCode Word8
- | OtherCode Word8
- | ExceptionCode FunctionCode
- data ExceptionCode
- data MB_Exception
- type TransactionId = Word16
- type ProtocolId = Word16
- type UnitId = Word8
- command :: TransactionId -> ProtocolId -> UnitId -> FunctionCode -> ByteString -> Socket -> ExceptT MB_Exception IO TCP_ADU
- readCoils :: TransactionId -> ProtocolId -> UnitId -> Word16 -> Word16 -> Socket -> ExceptT MB_Exception IO [Word8]
- readDiscreteInputs :: TransactionId -> ProtocolId -> UnitId -> Word16 -> Word16 -> Socket -> ExceptT MB_Exception IO [Word8]
- readHoldingRegisters :: TransactionId -> ProtocolId -> UnitId -> Word16 -> Word16 -> Socket -> ExceptT MB_Exception IO [Word16]
- readInputRegisters :: TransactionId -> ProtocolId -> UnitId -> Word16 -> Word16 -> Socket -> ExceptT MB_Exception IO [Word16]
- writeSingleCoil :: TransactionId -> ProtocolId -> UnitId -> Word16 -> Bool -> Socket -> ExceptT MB_Exception IO ()
- writeSingleRegister :: TransactionId -> ProtocolId -> UnitId -> Word16 -> Word16 -> Socket -> ExceptT MB_Exception IO ()
- writeMultipleRegisters :: TransactionId -> ProtocolId -> UnitId -> Word16 -> [Word16] -> Socket -> ExceptT MB_Exception IO Word16
Documentation
MODBUS TCP/IP Application Data Unit
See: MODBUS Application Protocol Specification V1.1b, section 4.1
Constructors
| TCP_ADU | |
Fields
| |
MODBUS Application Protocol Header
See: MODBUS Application Protocol Specification V1.1b, section 4.1
Constructors
| Header | |
Fields | |
data FunctionCode Source
The function code field of a MODBUS data unit is coded in one byte. Valid codes are in the range of 1 ... 255 decimal (the range 128 - 255 is reserved and used for exception responses). When a message is sent from a Client to a Server device the function code field tells the server what kind of action to perform. Function code 0 is not valid.
Sub-function codes are added to some function codes to define multiple actions.
See: MODBUS Application Protocol Specification V1.1b, sections 4.1 and 5
Constructors
| ReadCoils | See: MODBUS Application Protocol Specification V1.1b, section 6.1 |
| ReadDiscreteInputs | See: MODBUS Application Protocol Specification V1.1b, section 6.2 |
| ReadHoldingRegisters | See: MODBUS Application Protocol Specification V1.1b, section 6.3 |
| ReadInputRegisters | See: MODBUS Application Protocol Specification V1.1b, section 6.4 |
| WriteSingleCoil | See: MODBUS Application Protocol Specification V1.1b, section 6.5 |
| WriteSingleRegister | See: MODBUS Application Protocol Specification V1.1b, section 6.6 |
| ReadExceptionStatus | See: MODBUS Application Protocol Specification V1.1b, section 6.7 |
| Diagnostics | See: MODBUS Application Protocol Specification V1.1b, section 6.8 |
| GetCommEventCounter | See: MODBUS Application Protocol Specification V1.1b, section 6.9 |
| GetCommEventLog | See: MODBUS Application Protocol Specification V1.1b, section 6.10 |
| WriteMultipleCoils | See: MODBUS Application Protocol Specification V1.1b, section 6.11 |
| WriteMultipleRegisters | See: MODBUS Application Protocol Specification V1.1b, section 6.12 |
| ReportSlaveID | See: MODBUS Application Protocol Specification V1.1b, section 6.13 |
| ReadFileRecord | See: MODBUS Application Protocol Specification V1.1b, section 6.14 |
| WriteFileRecord | See: MODBUS Application Protocol Specification V1.1b, section 6.15 |
| MaskWriteRegister | See: MODBUS Application Protocol Specification V1.1b, section 6.16 |
| ReadWriteMultipleRegisters | See: MODBUS Application Protocol Specification V1.1b, section 6.17 |
| ReadFIFOQueue | See: MODBUS Application Protocol Specification V1.1b, section 6.18 |
| EncapsulatedInterfaceTransport | See: MODBUS Application Protocol Specification V1.1b, section 6.19 |
| UserDefinedCode Word8 | See: MODBUS Application Protocol Specification V1.1b, section 5 |
| ReservedCode Word8 | See: MODBUS Application Protocol Specification V1.1b, section 5 |
| OtherCode Word8 | |
| ExceptionCode FunctionCode |
data ExceptionCode Source
See: MODBUS Application Protocol Specification V1.1b, section 7
Constructors
| IllegalFunction | The function code received in the query is not an allowable action for the server (or slave). This may be because the function code is only applicable to newer devices, and was not implemented in the unit selected. It could also indicate that the server (or slave) is in the wrong state to process a request of this type, for example because it is unconfigured and is being asked to return register values. |
| IllegalDataAddress | The data address received in the query is not an allowable address for the server (or slave). More specifically, the combination of reference number and transfer length is invalid. For a controller with 100 registers, the PDU addresses the first register as 0, and the last one as 99. If a request is submitted with a starting register address of 96 and a quantity of registers of 4, then this request will successfully operate (address-wise at least) on registers 96, 97, 98, 99. If a request is submitted with a starting register address of 96 and a quantity of registers of 5, then this request will fail with Exception Code 0x02 "Illegal Data Address" since it attempts to operate on registers 96, 97, 98, 99 and 100, and there is no register with address 100. |
| IllegalDataValue | A value contained in the query data field is not an allowable value for server (or slave). This indicates a fault in the structure of the remainder of a complex request, such as that the implied length is incorrect. It specifically does NOT mean that a data item submitted for storage in a register has a value outside the expectation of the application program, since the MODBUS protocol is unaware of the significance of any particular value of any particular register. |
| SlaveDeviceFailure | An unrecoverable error occurred while the server (or slave) was attempting to perform the requested action. |
| Acknowledge | Specialized use in conjunction with programming commands. The server (or slave) has accepted the request and is processing it, but a long duration of time will be required to do so. This response is returned to prevent a timeout error from occurring in the client (or master). The client (or master) can next issue a Poll Program Complete message to determine if processing is completed. |
| SlaveDeviceBusy | Specialized use in conjunction with programming commands. The server (or slave) is engaged in processing a long–duration program command. The client (or master) should retransmit the message later when the server (or slave) is free. |
| MemoryParityError | Specialized use in conjunction with function codes
|
| GatewayPathUnavailable | Specialized use in conjunction with gateways, indicates that the gateway was unable to allocate an internal communication path from the input port to the output port for processing the request. Usually means that the gateway is misconfigured or overloaded. |
| GatewayTargetDeviceFailedToRespond | Specialized use in conjunction with gateways, indicates that no response was obtained from the target device. Usually means that the device is not present on the network. |
data MB_Exception Source
type TransactionId = Word16 Source
type ProtocolId = Word16 Source
Arguments
| :: TransactionId | |
| -> ProtocolId | |
| -> UnitId | |
| -> FunctionCode | PDU function code. |
| -> ByteString | PDU data. |
| -> Socket | |
| -> ExceptT MB_Exception IO TCP_ADU |
Sends a raw MODBUS command.
readCoils :: TransactionId -> ProtocolId -> UnitId -> Word16 -> Word16 -> Socket -> ExceptT MB_Exception IO [Word8] Source
readDiscreteInputs :: TransactionId -> ProtocolId -> UnitId -> Word16 -> Word16 -> Socket -> ExceptT MB_Exception IO [Word8] Source
Arguments
| :: TransactionId | |
| -> ProtocolId | |
| -> UnitId | |
| -> Word16 | Register starting address. |
| -> Word16 | Quantity of registers. |
| -> Socket | |
| -> ExceptT MB_Exception IO [Word16] |
Arguments
| :: TransactionId | |
| -> ProtocolId | |
| -> UnitId | |
| -> Word16 | Starting address. |
| -> Word16 | Quantity of input registers. |
| -> Socket | |
| -> ExceptT MB_Exception IO [Word16] |
writeSingleCoil :: TransactionId -> ProtocolId -> UnitId -> Word16 -> Bool -> Socket -> ExceptT MB_Exception IO () Source
Arguments
| :: TransactionId | |
| -> ProtocolId | |
| -> UnitId | |
| -> Word16 | Register address. |
| -> Word16 | Register value. |
| -> Socket | |
| -> ExceptT MB_Exception IO () |
Arguments
| :: TransactionId | |
| -> ProtocolId | |
| -> UnitId | |
| -> Word16 | Register starting address |
| -> [Word16] | Register values to be written |
| -> Socket | |
| -> ExceptT MB_Exception IO Word16 |