This is the description of the Delphi/Lazarus API bindings for the RS485 Bricklet. General information and technical specifications for the RS485 Bricklet are summarized in its hardware description.
An installation guide for the Delphi/Lazarus API bindings is part of their general description.
The example code below is Public Domain (CC0 1.0).
Download (ExampleLoopback.pas)
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 | program ExampleLoopback;
{ For this example connect the RX+/- pins to TX+/- pins on the same Bricklet
and configure the DIP switch on the Bricklet to full-duplex mode }
{$ifdef MSWINDOWS}{$apptype CONSOLE}{$endif}
{$ifdef FPC}{$mode OBJFPC}{$H+}{$endif}
uses
SysUtils, IPConnection, BrickletRS485;
type
TExample = class
private
ipcon: TIPConnection;
rs485: TBrickletRS485;
public
procedure ReadCB(sender: TBrickletRS485; const message_: TArrayOfChar);
procedure Execute;
end;
const
HOST = 'localhost';
PORT = 4223;
UID = 'XYZ'; { Change XYZ to the UID of your RS485 Bricklet }
var
e: TExample;
{ Callback procedure for read callback }
procedure TExample.ReadCB(sender: TBrickletRS485; const message_: TArrayOfChar);
var str: string;
begin
{ Assume that the message consists of ASCII characters and
convert it from an array of chars to a string }
SetString(str, PChar(@message_[0]), Length(message_));
WriteLn(Format('Message: "%s"', [str]));
end;
procedure TExample.Execute;
begin
{ Create IP connection }
ipcon := TIPConnection.Create;
{ Create device object }
rs485 := TBrickletRS485.Create(UID, ipcon);
{ Connect to brickd }
ipcon.Connect(HOST, PORT);
{ Don't use device before ipcon is connected }
{ Enable full-duplex mode }
rs485.SetRS485Configuration(115200, BRICKLET_RS485_PARITY_NONE,
BRICKLET_RS485_STOPBITS_1, BRICKLET_RS485_WORDLENGTH_8,
BRICKLET_RS485_DUPLEX_FULL);
{ Register read callback to procedure ReadCB }
rs485.OnRead := {$ifdef FPC}@{$endif}ReadCB;
{ Enable read callback }
rs485.EnableReadCallback;
{ Write "test" string }
rs485.Write(['t', 'e', 's', 't']);
WriteLn('Press key to exit');
ReadLn;
ipcon.Destroy; { Calls ipcon.Disconnect internally }
end;
begin
e := TExample.Create;
e.Execute;
e.Destroy;
end.
|
Download (ExampleModbusMaster.pas)
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 | program ExampleModbusMaster;
{$ifdef MSWINDOWS}{$apptype CONSOLE}{$endif}
{$ifdef FPC}{$mode OBJFPC}{$H+}{$endif}
uses
SysUtils, IPConnection, BrickletRS485;
type
TExample = class
private
ipcon: TIPConnection;
rs485: TBrickletRS485;
public
procedure ModbusMasterWriteSingleRegisterResponseCB(sender: TBrickletRS485;
const requestID: byte;
const exceptionCode: shortint);
procedure Execute;
end;
const
HOST = 'localhost';
PORT = 4223;
UID = 'XYZ'; { Change XYZ to the UID of your RS485 Bricklet }
var
e: TExample;
expectedRequestID: byte;
{ Callback procedure for Modbus master write single register response callback }
procedure TExample.ModbusMasterWriteSingleRegisterResponseCB(sender: TBrickletRS485;
const requestID: byte;
const exceptionCode: shortint);
begin
WriteLn(Format('Request ID: %d', [requestID]));
WriteLn(Format('Exception Code: %d', [exceptionCode]));
if (requestID <> expectedRequestID) then begin
WriteLn('Error: Unexpected request ID');
end;
end;
procedure TExample.Execute;
begin
{ Create IP connection }
ipcon := TIPConnection.Create;
{ Create device object }
rs485 := TBrickletRS485.Create(UID, ipcon);
{ Connect to brickd }
ipcon.Connect(HOST, PORT);
{ Don't use device before ipcon is connected }
{ Set operating mode to Modbus RTU master }
rs485.SetMode(BRICKLET_RS485_MODE_MODBUS_MASTER_RTU);
{ Modbus specific configuration:
- slave address = 1 (unused in master mode)
- master request timeout = 1000ms }
rs485.SetModbusConfiguration(1, 1000);
{ Register Modbus master write single register response callback to procedure
ModbusMasterWriteSingleRegisterResponseCB }
rs485.OnModbusMasterWriteSingleRegisterResponse := {$ifdef FPC}@{$endif}ModbusMasterWriteSingleRegisterResponseCB;
{ Write 65535 to register 42 of slave 17 }
expectedRequestID := rs485.ModbusMasterWriteSingleRegister(17, 42, 65535);
WriteLn('Press key to exit');
ReadLn;
ipcon.Destroy; { Calls ipcon.Disconnect internally }
end;
begin
e := TExample.Create;
e.Execute;
e.Destroy;
end.
|
Download (ExampleModbusSlave.pas)
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 | program ExampleModbusSlave;
{$ifdef MSWINDOWS}{$apptype CONSOLE}{$endif}
{$ifdef FPC}{$mode OBJFPC}{$H+}{$endif}
uses
SysUtils, IPConnection, BrickletRS485;
type
TExample = class
private
ipcon: TIPConnection;
rs485: TBrickletRS485;
public
procedure ModbusSlaveWriteSingleRegisterRequestCB(sender: TBrickletRS485;
const requestID: byte;
const registerAddress: longword;
const registerValue: word);
procedure Execute;
end;
const
HOST = 'localhost';
PORT = 4223;
UID = 'XYZ'; { Change XYZ to the UID of your RS485 Bricklet }
var
e: TExample;
{ Callback procedure for Modbus slave write single register request callback }
procedure TExample.ModbusSlaveWriteSingleRegisterRequestCB(sender: TBrickletRS485;
const requestID: byte;
const registerAddress: longword;
const registerValue: word);
begin
WriteLn(Format('Request ID: %d', [requestID]));
WriteLn(Format('Register Address: %d', [registerAddress]));
WriteLn(Format('Register Value: %d', [registerValue]));
if (registerAddress <> 42) then begin
WriteLn('Error: Invalid register address');
sender.ModbusSlaveReportException(requestID, BRICKLET_RS485_EXCEPTION_CODE_ILLEGAL_DATA_ADDRESS);
end
else begin
sender.ModbusSlaveAnswerWriteSingleRegisterRequest(requestID);
end
end;
procedure TExample.Execute;
begin
{ Create IP connection }
ipcon := TIPConnection.Create;
{ Create device object }
rs485 := TBrickletRS485.Create(UID, ipcon);
{ Connect to brickd }
ipcon.Connect(HOST, PORT);
{ Don't use device before ipcon is connected }
{ Set operating mode to Modbus RTU slave }
rs485.SetMode(BRICKLET_RS485_MODE_MODBUS_SLAVE_RTU);
{ Modbus specific configuration:
- slave address = 17
- master request timeout = 0ms (unused in slave mode) }
rs485.SetModbusConfiguration(17, 0);
{ Register Modbus slave write single register request callback to procedure
ModbusSlaveWriteSingleRegisterRequestCB }
rs485.OnModbusSlaveWriteSingleRegisterRequest := {$ifdef FPC}@{$endif}ModbusSlaveWriteSingleRegisterRequestCB;
WriteLn('Press key to exit');
ReadLn;
ipcon.Destroy; { Calls ipcon.Disconnect internally }
end;
begin
e := TExample.Create;
e.Execute;
e.Destroy;
end.
|
Since Delphi does not support multiple return values directly, we use the
out
keyword to return multiple values from a function.
All functions and procedures listed below are thread-safe.
TBrickletRS485.
Create
(const uid: string; ipcon: TIPConnection)¶Parameters: |
|
---|---|
Returns: |
|
Creates an object with the unique device ID uid
:
rs485 := TBrickletRS485.Create('YOUR_DEVICE_UID', ipcon);
This object can then be used after the IP Connection is connected.
TBrickletRS485.
Write
(const message: array of char): word¶Parameters: |
|
---|---|
Returns: |
|
Writes characters to the RS485 interface. The characters can be binary data, ASCII or similar is not necessary.
The return value is the number of characters that were written.
See SetRS485Configuration
for configuration possibilities
regarding baudrate, parity and so on.
TBrickletRS485.
Read
(const length: word): array of char¶Parameters: |
|
---|---|
Returns: |
|
Returns up to length characters from receive buffer.
Instead of polling with this function, you can also use
callbacks. But note that this function will return available
data only when the read callback is disabled.
See EnableReadCallback
and OnRead
callback.
TBrickletRS485.
SetRS485Configuration
(const baudrate: longword; const parity: byte; const stopbits: byte; const wordlength: byte; const duplex: byte)¶Parameters: |
|
---|
Sets the configuration for the RS485 communication.
The following constants are available for this function:
For parity:
For stopbits:
For wordlength:
For duplex:
TBrickletRS485.
GetRS485Configuration
(out baudrate: longword; out parity: byte; out stopbits: byte; out wordlength: byte; out duplex: byte)¶Output Parameters: |
|
---|
Returns the configuration as set by SetRS485Configuration
.
The following constants are available for this function:
For parity:
For stopbits:
For wordlength:
For duplex:
TBrickletRS485.
SetModbusConfiguration
(const slaveAddress: byte; const masterRequestTimeout: longword)¶Parameters: |
|
---|
Sets the configuration for the RS485 Modbus communication. Available options:
TBrickletRS485.
GetModbusConfiguration
(out slaveAddress: byte; out masterRequestTimeout: longword)¶Output Parameters: |
|
---|
Returns the configuration as set by SetModbusConfiguration
.
TBrickletRS485.
SetMode
(const mode: byte)¶Parameters: |
|
---|
Sets the mode of the Bricklet in which it operates. Available options are
The following constants are available for this function:
For mode:
TBrickletRS485.
GetMode
: byte¶Returns: |
|
---|
Returns the configuration as set by SetMode
.
The following constants are available for this function:
For mode:
TBrickletRS485.
SetCommunicationLEDConfig
(const config: byte)¶Parameters: |
|
---|
Sets the communication LED configuration. By default the LED shows RS485 communication traffic by flickering.
You can also turn the LED permanently on/off or show a heartbeat.
If the Bricklet is in bootloader mode, the LED is off.
The following constants are available for this function:
For config:
TBrickletRS485.
GetCommunicationLEDConfig
: byte¶Returns: |
|
---|
Returns the configuration as set by SetCommunicationLEDConfig
The following constants are available for this function:
For config:
TBrickletRS485.
SetErrorLEDConfig
(const config: byte)¶Parameters: |
|
---|
Sets the error LED configuration.
By default the error LED turns on if there is any error (see OnErrorCount
callback). If you call this function with the SHOW ERROR option again, the LED
will turn off until the next error occurs.
You can also turn the LED permanently on/off or show a heartbeat.
If the Bricklet is in bootloader mode, the LED is off.
The following constants are available for this function:
For config:
TBrickletRS485.
GetErrorLEDConfig
: byte¶Returns: |
|
---|
Returns the configuration as set by SetErrorLEDConfig
.
The following constants are available for this function:
For config:
TBrickletRS485.
SetBufferConfig
(const sendBufferSize: word; const receiveBufferSize: word)¶Parameters: |
|
---|
Sets the send and receive buffer size in byte. In sum there is 10240 byte (10KiB) buffer available and the minimum buffer size is 1024 byte (1KiB) for both.
The current buffer content is lost if this function is called.
The send buffer holds data that was given by Write
and
could not be written yet. The receive buffer holds data that is
received through RS485 but could not yet be send to the
user, either by Read
or through OnRead
callback.
TBrickletRS485.
GetBufferConfig
(out sendBufferSize: word; out receiveBufferSize: word)¶Output Parameters: |
|
---|
Returns the buffer configuration as set by SetBufferConfig
.
TBrickletRS485.
GetBufferStatus
(out sendBufferUsed: word; out receiveBufferUsed: word)¶Output Parameters: |
|
---|
Returns the currently used bytes for the send and received buffer.
See SetBufferConfig
for buffer size configuration.
TBrickletRS485.
GetErrorCount
(out overrunErrorCount: longword; out parityErrorCount: longword)¶Output Parameters: |
|
---|
Returns the current number of overrun and parity errors.
TBrickletRS485.
GetModbusCommonErrorCount
(out timeoutErrorCount: longword; out checksumErrorCount: longword; out frameTooBigErrorCount: longword; out illegalFunctionErrorCount: longword; out illegalDataAddressErrorCount: longword; out illegalDataValueErrorCount: longword; out slaveDeviceFailureErrorCount: longword)¶Output Parameters: |
|
---|
Returns the current number of errors occurred in Modbus mode.
TBrickletRS485.
ModbusSlaveReportException
(const requestID: byte; const exceptionCode: shortint)¶Parameters: |
|
---|
In Modbus slave mode this function can be used to report a Modbus exception for a Modbus master request.
The following constants are available for this function:
For exceptionCode:
TBrickletRS485.
ModbusSlaveAnswerReadCoilsRequest
(const requestID: byte; const coils: array of boolean)¶Parameters: |
|
---|
In Modbus slave mode this function can be used to answer a master request to read coils.
This function must be called from the OnModbusSlaveReadCoilsRequest
callback
with the Request ID as provided by the argument of the callback.
TBrickletRS485.
ModbusMasterReadCoils
(const slaveAddress: byte; const startingAddress: longword; const count: word): byte¶Parameters: |
|
---|---|
Returns: |
|
In Modbus master mode this function can be used to read coils from a slave. This function creates a Modbus function code 1 request.
Upon success the function will return a non-zero request ID which will represent the current request initiated by the Modbus master. In case of failure the returned request ID will be 0.
When successful this function will also invoke the OnModbusMasterReadCoilsResponse
callback. In this callback the Request ID provided by the callback argument must be
matched with the Request ID returned from this function to verify that the callback
is indeed for a particular request.
TBrickletRS485.
ModbusSlaveAnswerReadHoldingRegistersRequest
(const requestID: byte; const holdingRegisters: array of word)¶Parameters: |
|
---|
In Modbus slave mode this function can be used to answer a master request to read holding registers.
This function must be called from the OnModbusSlaveReadHoldingRegistersRequest
callback with the Request ID as provided by the argument of the callback.
TBrickletRS485.
ModbusMasterReadHoldingRegisters
(const slaveAddress: byte; const startingAddress: longword; const count: word): byte¶Parameters: |
|
---|---|
Returns: |
|
In Modbus master mode this function can be used to read holding registers from a slave. This function creates a Modbus function code 3 request.
Upon success the function will return a non-zero request ID which will represent the current request initiated by the Modbus master. In case of failure the returned request ID will be 0.
When successful this function will also invoke the OnModbusMasterReadHoldingRegistersResponse
callback. In this callback the Request ID provided by the callback argument must be matched
with the Request ID returned from this function to verify that the callback is indeed for a
particular request.
TBrickletRS485.
ModbusSlaveAnswerWriteSingleCoilRequest
(const requestID: byte)¶Parameters: |
|
---|
In Modbus slave mode this function can be used to answer a master request to write a single coil.
This function must be called from the OnModbusSlaveWriteSingleCoilRequest
callback with the Request ID as provided by the arguments of the callback.
TBrickletRS485.
ModbusMasterWriteSingleCoil
(const slaveAddress: byte; const coilAddress: longword; const coilValue: boolean): byte¶Parameters: |
|
---|---|
Returns: |
|
In Modbus master mode this function can be used to write a single coil of a slave. This function creates a Modbus function code 5 request.
Upon success the function will return a non-zero request ID which will represent the current request initiated by the Modbus master. In case of failure the returned request ID will be 0.
When successful this function will also invoke the OnModbusMasterWriteSingleCoilResponse
callback. In this callback the Request ID provided by the callback argument must be matched
with the Request ID returned from this function to verify that the callback is indeed for a
particular request.
TBrickletRS485.
ModbusSlaveAnswerWriteSingleRegisterRequest
(const requestID: byte)¶Parameters: |
|
---|
In Modbus slave mode this function can be used to answer a master request to write a single register.
This function must be called from the OnModbusSlaveWriteSingleRegisterRequest
callback with the Request ID, Register Address and Register Value as provided by
the arguments of the callback.
TBrickletRS485.
ModbusMasterWriteSingleRegister
(const slaveAddress: byte; const registerAddress: longword; const registerValue: word): byte¶Parameters: |
|
---|---|
Returns: |
|
In Modbus master mode this function can be used to write a single holding register of a slave. This function creates a Modbus function code 6 request.
Upon success the function will return a non-zero request ID which will represent the current request initiated by the Modbus master. In case of failure the returned request ID will be 0.
When successful this function will also invoke the OnModbusMasterWriteSingleRegisterResponse
callback. In this callback the Request ID provided by the callback argument must be matched
with the Request ID returned from this function to verify that the callback is indeed for a
particular request.
TBrickletRS485.
ModbusSlaveAnswerWriteMultipleCoilsRequest
(const requestID: byte)¶Parameters: |
|
---|
In Modbus slave mode this function can be used to answer a master request to write multiple coils.
This function must be called from the OnModbusSlaveWriteMultipleCoilsRequest
callback with the Request ID of the callback.
TBrickletRS485.
ModbusMasterWriteMultipleCoils
(const slaveAddress: byte; const startingAddress: longword; const coils: array of boolean): byte¶Parameters: |
|
---|---|
Returns: |
|
In Modbus master mode this function can be used to write multiple coils of a slave. This function creates a Modbus function code 15 request.
Upon success the function will return a non-zero request ID which will represent the current request initiated by the Modbus master. In case of failure the returned request ID will be 0.
When successful this function will also invoke the OnModbusMasterWriteMultipleCoilsResponse
callback. In this callback the Request ID provided by the callback argument must be matched
with the Request ID returned from this function to verify that the callback is indeed for a
particular request.
TBrickletRS485.
ModbusSlaveAnswerWriteMultipleRegistersRequest
(const requestID: byte)¶Parameters: |
|
---|
In Modbus slave mode this function can be used to answer a master request to write multiple registers.
This function must be called from the OnModbusSlaveWriteMultipleRegistersRequest
callback with the Request ID of the callback.
TBrickletRS485.
ModbusMasterWriteMultipleRegisters
(const slaveAddress: byte; const startingAddress: longword; const registers: array of word): byte¶Parameters: |
|
---|---|
Returns: |
|
In Modbus master mode this function can be used to write multiple registers of a slave. This function creates a Modbus function code 16 request.
Upon success the function will return a non-zero request ID which will represent the current request initiated by the Modbus master. In case of failure the returned request ID will be 0.
When successful this function will also invoke the OnModbusMasterWriteMultipleRegistersResponse
callback. In this callback the Request ID provided by the callback argument must be matched
with the Request ID returned from this function to verify that the callback is indeed for a
particular request.
TBrickletRS485.
ModbusSlaveAnswerReadDiscreteInputsRequest
(const requestID: byte; const discreteInputs: array of boolean)¶Parameters: |
|
---|
In Modbus slave mode this function can be used to answer a master request to read discrete inputs.
This function must be called from the OnModbusSlaveReadDiscreteInputsRequest
callback with the Request ID as provided by the argument of the callback.
TBrickletRS485.
ModbusMasterReadDiscreteInputs
(const slaveAddress: byte; const startingAddress: longword; const count: word): byte¶Parameters: |
|
---|---|
Returns: |
|
In Modbus master mode this function can be used to read discrete inputs from a slave. This function creates a Modbus function code 2 request.
Upon success the function will return a non-zero request ID which will represent the current request initiated by the Modbus master. In case of failure the returned request ID will be 0.
When successful this function will also invoke the OnModbusMasterReadDiscreteInputsResponse
callback. In this callback the Request ID provided by the callback argument must be matched
with the Request ID returned from this function to verify that the callback is indeed for a
particular request.
TBrickletRS485.
ModbusSlaveAnswerReadInputRegistersRequest
(const requestID: byte; const inputRegisters: array of word)¶Parameters: |
|
---|
In Modbus slave mode this function can be used to answer a master request to read input registers.
This function must be called from the OnModbusSlaveReadInputRegistersRequest
callback
with the Request ID as provided by the argument of the callback.
TBrickletRS485.
ModbusMasterReadInputRegisters
(const slaveAddress: byte; const startingAddress: longword; const count: word): byte¶Parameters: |
|
---|---|
Returns: |
|
In Modbus master mode this function can be used to read input registers from a slave. This function creates a Modbus function code 4 request.
Upon success the function will return a non-zero request ID which will represent the current request initiated by the Modbus master. In case of failure the returned request ID will be 0.
When successful this function will also invoke the OnModbusMasterReadInputRegistersResponse
callback. In this callback the Request ID provided by the callback argument must be matched
with the Request ID returned from this function to verify that the callback is indeed for a
particular request.
TBrickletRS485.
GetSPITFPErrorCount
(out errorCountAckChecksum: longword; out errorCountMessageChecksum: longword; out errorCountFrame: longword; out errorCountOverflow: longword)¶Output Parameters: |
|
---|
Returns the error count for the communication between Brick and Bricklet.
The errors are divided into
The errors counts are for errors that occur on the Bricklet side. All Bricks have a similar function that returns the errors on the Brick side.
TBrickletRS485.
SetStatusLEDConfig
(const config: byte)¶Parameters: |
|
---|
Sets the status LED configuration. By default the LED shows communication traffic between Brick and Bricklet, it flickers once for every 10 received data packets.
You can also turn the LED permanently on/off or show a heartbeat.
If the Bricklet is in bootloader mode, the LED is will show heartbeat by default.
The following constants are available for this function:
For config:
TBrickletRS485.
GetStatusLEDConfig
: byte¶Returns: |
|
---|
Returns the configuration as set by SetStatusLEDConfig
The following constants are available for this function:
For config:
TBrickletRS485.
GetChipTemperature
: smallint¶Returns: |
|
---|
Returns the temperature as measured inside the microcontroller. The value returned is not the ambient temperature!
The temperature is only proportional to the real temperature and it has bad accuracy. Practically it is only useful as an indicator for temperature changes.
TBrickletRS485.
Reset
¶Calling this function will reset the Bricklet. All configurations will be lost.
After a reset you have to create new device objects, calling functions on the existing ones will result in undefined behavior!
TBrickletRS485.
GetIdentity
(out uid: string; out connectedUid: string; out position: char; out hardwareVersion: array [0..2] of byte; out firmwareVersion: array [0..2] of byte; out deviceIdentifier: word)¶Output Parameters: |
|
---|
Returns the UID, the UID where the Bricklet is connected to, the position, the hardware and firmware version as well as the device identifier.
The position can be 'a', 'b', 'c', 'd', 'e', 'f', 'g' or 'h' (Bricklet Port). A Bricklet connected to an Isolator Bricklet is always at position 'z'.
The device identifier numbers can be found here. There is also a constant for the device identifier of this Bricklet.
TBrickletRS485.
EnableReadCallback
¶Enables the OnRead
callback. This will disable the OnFrameReadable
callback.
By default the callback is disabled.
TBrickletRS485.
DisableReadCallback
¶Disables the OnRead
callback.
By default the callback is disabled.
TBrickletRS485.
IsReadCallbackEnabled
: boolean¶Returns: |
|
---|
Returns true if the OnRead
callback is enabled,
false otherwise.
TBrickletRS485.
EnableErrorCountCallback
¶Enables the OnErrorCount
callback.
By default the callback is disabled.
TBrickletRS485.
DisableErrorCountCallback
¶Disables the OnErrorCount
callback.
By default the callback is disabled.
TBrickletRS485.
IsErrorCountCallbackEnabled
: boolean¶Returns: |
|
---|
Returns true if the OnErrorCount
callback is enabled,
false otherwise.
TBrickletRS485.
SetFrameReadableCallbackConfiguration
(const frameSize: word)¶Parameters: |
|
---|
Configures the OnFrameReadable
callback. The frame size is the number of bytes, that have to be readable to trigger the callback.
A frame size of 0 disables the callback. A frame size greater than 0 enables the callback and disables the OnRead
callback.
By default the callback is disabled.
New in version 2.0.5 (Plugin).
TBrickletRS485.
GetFrameReadableCallbackConfiguration
: word¶Returns: |
|
---|
Returns the callback configuration as set by SetFrameReadableCallbackConfiguration
.
New in version 2.0.5 (Plugin).
Callbacks can be registered to receive time critical or recurring data from the device. The registration is done by assigning a procedure to an callback property of the device object:
procedure TExample.MyCallback(sender: TBrickletRS485; const value: longint); begin WriteLn(Format('Value: %d', [value])); end; rs485.OnExample := {$ifdef FPC}@{$endif}example.MyCallback;
The available callback properties and their parameter types are described below.
Note
Using callbacks for recurring events is always preferred compared to using getters. It will use less USB bandwidth and the latency will be a lot better, since there is no round trip time.
TBrickletRS485.
OnRead
¶procedure(sender: TBrickletRS485; const message: array of char) of object;
Callback Parameters: |
|
---|
This callback is called if new data is available.
To enable this callback, use EnableReadCallback
.
Note
If reconstructing the value fails, the callback is triggered with nil for message.
TBrickletRS485.
OnErrorCount
¶procedure(sender: TBrickletRS485; const overrunErrorCount: longword; const parityErrorCount: longword) of object;
Callback Parameters: |
|
---|
This callback is called if a new error occurs. It returns the current overrun and parity error count.
TBrickletRS485.
OnModbusSlaveReadCoilsRequest
¶procedure(sender: TBrickletRS485; const requestID: byte; const startingAddress: longword; const count: word) of object;
Callback Parameters: |
|
---|
This callback is called only in Modbus slave mode when the slave receives a valid request from a Modbus master to read coils. The parameters are request ID of the request, the number of the first coil to be read and the number of coils to be read as received by the request. The number of the first coil is called starting address for backwards compatibility reasons. It is not an address, but instead a coil number in the range of 1 to 65536.
To send a response of this request use ModbusSlaveAnswerReadCoilsRequest
.
TBrickletRS485.
OnModbusMasterReadCoilsResponse
¶procedure(sender: TBrickletRS485; const requestID: byte; const exceptionCode: shortint; const coils: array of boolean) of object;
Callback Parameters: |
|
---|
This callback is called only in Modbus master mode when the master receives a valid response of a request to read coils.
The parameters are request ID of the request, exception code of the response and the data as received by the response.
Any non-zero exception code indicates a problem. If the exception code
is greater than 0 then the number represents a Modbus exception code. If it is
less than 0 then it represents other errors. For example, -1 indicates that
the request timed out or that the master did not receive any valid response of the
request within the master request timeout period as set by
SetModbusConfiguration
.
Note
If reconstructing the value fails, the callback is triggered with nil for coils.
The following constants are available for this function:
For exceptionCode:
TBrickletRS485.
OnModbusSlaveReadHoldingRegistersRequest
¶procedure(sender: TBrickletRS485; const requestID: byte; const startingAddress: longword; const count: word) of object;
Callback Parameters: |
|
---|
This callback is called only in Modbus slave mode when the slave receives a valid request from a Modbus master to read holding registers. The parameters are request ID of the request, the number of the first holding register to be read and the number of holding registers to be read as received by the request. The number of the first holding register is called starting address for backwards compatibility reasons. It is not an address, but instead a holding register number in the range of 1 to 65536. The prefix digit 4 (for holding register) is omitted.
To send a response of this request use ModbusSlaveAnswerReadHoldingRegistersRequest
.
TBrickletRS485.
OnModbusMasterReadHoldingRegistersResponse
¶procedure(sender: TBrickletRS485; const requestID: byte; const exceptionCode: shortint; const holdingRegisters: array of word) of object;
Callback Parameters: |
|
---|
This callback is called only in Modbus master mode when the master receives a valid response of a request to read holding registers.
The parameters are request ID of the request, exception code of the response and the data as received by the response.
Any non-zero exception code indicates a problem. If the exception
code is greater than 0 then the number represents a Modbus exception code. If
it is less than 0 then it represents other errors. For example, -1 indicates that
the request timed out or that the master did not receive any valid response of the
request within the master request timeout period as set by
SetModbusConfiguration
.
Note
If reconstructing the value fails, the callback is triggered with nil for holdingRegisters.
The following constants are available for this function:
For exceptionCode:
TBrickletRS485.
OnModbusSlaveWriteSingleCoilRequest
¶procedure(sender: TBrickletRS485; const requestID: byte; const coilAddress: longword; const coilValue: boolean) of object;
Callback Parameters: |
|
---|
This callback is called only in Modbus slave mode when the slave receives a valid request from a Modbus master to write a single coil. The parameters are request ID of the request, the number of the coil and the value of coil to be written as received by the request. The number of the coil is called coil address for backwards compatibility reasons. It is not an address, but instead a coil number in the range of 1 to 65536.
To send a response of this request use ModbusSlaveAnswerWriteSingleCoilRequest
.
TBrickletRS485.
OnModbusMasterWriteSingleCoilResponse
¶procedure(sender: TBrickletRS485; const requestID: byte; const exceptionCode: shortint) of object;
Callback Parameters: |
|
---|
This callback is called only in Modbus master mode when the master receives a valid response of a request to write a single coil.
The parameters are request ID of the request and exception code of the response.
Any non-zero exception code indicates a problem.
If the exception code is greater than 0 then the number represents a Modbus
exception code. If it is less than 0 then it represents other errors. For
example, -1 indicates that the request timed out or that the master did not receive
any valid response of the request within the master request timeout period as set
by SetModbusConfiguration
.
The following constants are available for this function:
For exceptionCode:
TBrickletRS485.
OnModbusSlaveWriteSingleRegisterRequest
¶procedure(sender: TBrickletRS485; const requestID: byte; const registerAddress: longword; const registerValue: word) of object;
Callback Parameters: |
|
---|
This callback is called only in Modbus slave mode when the slave receives a valid request from a Modbus master to write a single holding register. The parameters are request ID of the request, the number of the holding register and the register value to be written as received by the request. The number of the holding register is called starting address for backwards compatibility reasons. It is not an address, but instead a holding register number in the range of 1 to 65536. The prefix digit 4 (for holding register) is omitted.
To send a response of this request use ModbusSlaveAnswerWriteSingleRegisterRequest
.
TBrickletRS485.
OnModbusMasterWriteSingleRegisterResponse
¶procedure(sender: TBrickletRS485; const requestID: byte; const exceptionCode: shortint) of object;
Callback Parameters: |
|
---|
This callback is called only in Modbus master mode when the master receives a valid response of a request to write a single register.
The parameters are request ID of the request and exception code of the response.
Any non-zero exception code
indicates a problem. If the exception code is greater than 0 then the number
represents a Modbus exception code. If it is less than 0 then it represents
other errors. For example, -1 indicates that the request timed out or that the
master did not receive any valid response of the request within the master request
timeout period as set by SetModbusConfiguration
.
The following constants are available for this function:
For exceptionCode:
TBrickletRS485.
OnModbusSlaveWriteMultipleCoilsRequest
¶procedure(sender: TBrickletRS485; const requestID: byte; const startingAddress: longword; const coils: array of boolean) of object;
Callback Parameters: |
|
---|
This callback is called only in Modbus slave mode when the slave receives a valid request from a Modbus master to write multiple coils. The parameters are request ID of the request, the number of the first coil and the data to be written as received by the request. The number of the first coil is called starting address for backwards compatibility reasons. It is not an address, but instead a coil number in the range of 1 to 65536.
To send a response of this request use ModbusSlaveAnswerWriteMultipleCoilsRequest
.
Note
If reconstructing the value fails, the callback is triggered with nil for coils.
TBrickletRS485.
OnModbusMasterWriteMultipleCoilsResponse
¶procedure(sender: TBrickletRS485; const requestID: byte; const exceptionCode: shortint) of object;
Callback Parameters: |
|
---|
This callback is called only in Modbus master mode when the master receives a valid response of a request to read coils.
The parameters are request ID of the request and exception code of the response.
Any non-zero exception code
indicates a problem. If the exception code is greater than 0 then the number
represents a Modbus exception code. If it is less than 0 then it represents
other errors. For example, -1 indicates that the request timedout or that the
master did not receive any valid response of the request within the master request
timeout period as set by SetModbusConfiguration
.
The following constants are available for this function:
For exceptionCode:
TBrickletRS485.
OnModbusSlaveWriteMultipleRegistersRequest
¶procedure(sender: TBrickletRS485; const requestID: byte; const startingAddress: longword; const registers: array of word) of object;
Callback Parameters: |
|
---|
This callback is called only in Modbus slave mode when the slave receives a valid request from a Modbus master to write multiple holding registers. The parameters are request ID of the request, the number of the first holding register and the data to be written as received by the request. The number of the first holding register is called starting address for backwards compatibility reasons. It is not an address, but instead a holding register number in the range of 1 to 65536. The prefix digit 4 (for holding register) is omitted.
To send a response of this request use ModbusSlaveAnswerWriteMultipleRegistersRequest
.
Note
If reconstructing the value fails, the callback is triggered with nil for registers.
TBrickletRS485.
OnModbusMasterWriteMultipleRegistersResponse
¶procedure(sender: TBrickletRS485; const requestID: byte; const exceptionCode: shortint) of object;
Callback Parameters: |
|
---|
This callback is called only in Modbus master mode when the master receives a valid response of a request to write multiple registers.
The parameters are request ID of the request and exception code of the response.
Any non-zero
exception code indicates a problem. If the exception code is greater than 0 then
the number represents a Modbus exception code. If it is less than 0 then it
represents other errors. For example, -1 indicates that the request timedout or
that the master did not receive any valid response of the request within the master
request timeout period as set by SetModbusConfiguration
.
The following constants are available for this function:
For exceptionCode:
TBrickletRS485.
OnModbusSlaveReadDiscreteInputsRequest
¶procedure(sender: TBrickletRS485; const requestID: byte; const startingAddress: longword; const count: word) of object;
Callback Parameters: |
|
---|
This callback is called only in Modbus slave mode when the slave receives a valid request from a Modbus master to read discrete inputs. The parameters are request ID of the request, the number of the first discrete input and the number of discrete inputs to be read as received by the request. The number of the first discrete input is called starting address for backwards compatibility reasons. It is not an address, but instead a discrete input number in the range of 1 to 65536. The prefix digit 1 (for discrete input) is omitted.
To send a response of this request use ModbusSlaveAnswerReadDiscreteInputsRequest
.
TBrickletRS485.
OnModbusMasterReadDiscreteInputsResponse
¶procedure(sender: TBrickletRS485; const requestID: byte; const exceptionCode: shortint; const discreteInputs: array of boolean) of object;
Callback Parameters: |
|
---|
This callback is called only in Modbus master mode when the master receives a valid response of a request to read discrete inputs.
The parameters are request ID of the request, exception code of the response and the data as received by the response.
Any non-zero exception code indicates a problem. If the exception
code is greater than 0 then the number represents a Modbus exception code. If
it is less than 0 then it represents other errors. For example, -1 indicates that
the request timedout or that the master did not receive any valid response of the
request within the master request timeout period as set by
SetModbusConfiguration
.
Note
If reconstructing the value fails, the callback is triggered with nil for discreteInputs.
The following constants are available for this function:
For exceptionCode:
TBrickletRS485.
OnModbusSlaveReadInputRegistersRequest
¶procedure(sender: TBrickletRS485; const requestID: byte; const startingAddress: longword; const count: word) of object;
Callback Parameters: |
|
---|
This callback is called only in Modbus slave mode when the slave receives a valid request from a Modbus master to read input registers. The parameters are request ID of the request, the number of the first input register and the number of input registers to be read as received by the request. The number of the first input register is called starting address for backwards compatibility reasons. It is not an address, but instead a input register number in the range of 1 to 65536. The prefix digit 3 (for input register) is omitted.
To send a response of this request use ModbusSlaveAnswerReadInputRegistersRequest
.
TBrickletRS485.
OnModbusMasterReadInputRegistersResponse
¶procedure(sender: TBrickletRS485; const requestID: byte; const exceptionCode: shortint; const inputRegisters: array of word) of object;
Callback Parameters: |
|
---|
This callback is called only in Modbus master mode when the master receives a valid response of a request to read input registers.
The parameters are request ID of the request, exception code of the response and the data as received by the response.
Any non-zero exception code indicates a problem. If the exception
code is greater than 0 then the number represents a Modbus exception code. If
it is less than 0 then it represents other errors. For example, -1 indicates that
the request timedout or that the master did not receive any valid response of the
request within the master request timeout period as set by
SetModbusConfiguration
.
Note
If reconstructing the value fails, the callback is triggered with nil for inputRegisters.
The following constants are available for this function:
For exceptionCode:
TBrickletRS485.
OnFrameReadable
¶procedure(sender: TBrickletRS485; const frameCount: word) of object;
Callback Parameters: |
|
---|
This callback is called if at least one frame of data is readable. The frame size is configured with SetFrameReadableCallbackConfiguration
.
The frame count parameter is the number of frames that can be read.
This callback is triggered only once until Read
is called. This means, that if you have configured a frame size of X bytes,
you can read exactly X bytes using the Read
function, every time the callback triggers without checking the frame count parameter.
New in version 2.0.5 (Plugin).
Virtual functions don't communicate with the device itself, but operate only on the API bindings device object. They can be called without the corresponding IP Connection object being connected.
TBrickletRS485.
GetAPIVersion
: array [0..2] of byte¶Output Parameters: |
|
---|
Returns the version of the API definition implemented by this API bindings. This is neither the release version of this API bindings nor does it tell you anything about the represented Brick or Bricklet.
TBrickletRS485.
GetResponseExpected
(const functionId: byte): boolean¶Parameters: |
|
---|---|
Returns: |
|
Returns the response expected flag for the function specified by the function ID parameter. It is true if the function is expected to send a response, false otherwise.
For getter functions this is enabled by default and cannot be disabled,
because those functions will always send a response. For callback configuration
functions it is enabled by default too, but can be disabled by
SetResponseExpected
. For setter functions it is disabled by default
and can be enabled.
Enabling the response expected flag for a setter function allows to detect timeouts and other error conditions calls of this setter as well. The device will then send a response for this purpose. If this flag is disabled for a setter function then no response is sent and errors are silently ignored, because they cannot be detected.
The following constants are available for this function:
For functionId:
TBrickletRS485.
SetResponseExpected
(const functionId: byte; const responseExpected: boolean)¶Parameters: |
|
---|
Changes the response expected flag of the function specified by the function ID parameter. This flag can only be changed for setter (default value: false) and callback configuration functions (default value: true). For getter functions it is always enabled.
Enabling the response expected flag for a setter function allows to detect timeouts and other error conditions calls of this setter as well. The device will then send a response for this purpose. If this flag is disabled for a setter function then no response is sent and errors are silently ignored, because they cannot be detected.
The following constants are available for this function:
For functionId:
TBrickletRS485.
SetResponseExpectedAll
(const responseExpected: boolean)¶Parameters: |
|
---|
Changes the response expected flag for all setter and callback configuration functions of this device at once.
Internal functions are used for maintenance tasks such as flashing a new firmware of changing the UID of a Bricklet. These task should be performed using Brick Viewer instead of using the internal functions directly.
TBrickletRS485.
SetBootloaderMode
(const mode: byte): byte¶Parameters: |
|
---|---|
Returns: |
|
Sets the bootloader mode and returns the status after the requested mode change was instigated.
You can change from bootloader mode to firmware mode and vice versa. A change from bootloader mode to firmware mode will only take place if the entry function, device identifier and CRC are present and correct.
This function is used by Brick Viewer during flashing. It should not be necessary to call it in a normal user program.
The following constants are available for this function:
For mode:
For status:
TBrickletRS485.
GetBootloaderMode
: byte¶Returns: |
|
---|
Returns the current bootloader mode, see SetBootloaderMode
.
The following constants are available for this function:
For mode:
TBrickletRS485.
SetWriteFirmwarePointer
(const pointer: longword)¶Parameters: |
|
---|
Sets the firmware pointer for WriteFirmware
. The pointer has
to be increased by chunks of size 64. The data is written to flash
every 4 chunks (which equals to one page of size 256).
This function is used by Brick Viewer during flashing. It should not be necessary to call it in a normal user program.
TBrickletRS485.
WriteFirmware
(const data: array [0..63] of byte): byte¶Parameters: |
|
---|---|
Returns: |
|
Writes 64 Bytes of firmware at the position as written by
SetWriteFirmwarePointer
before. The firmware is written
to flash every 4 chunks.
You can only write firmware in bootloader mode.
This function is used by Brick Viewer during flashing. It should not be necessary to call it in a normal user program.
TBrickletRS485.
WriteUID
(const uid: longword)¶Parameters: |
|
---|
Writes a new UID into flash. If you want to set a new UID you have to decode the Base58 encoded UID string into an integer first.
We recommend that you use Brick Viewer to change the UID.
TBrickletRS485.
ReadUID
: longword¶Returns: |
|
---|
Returns the current UID as an integer. Encode as Base58 to get the usual string version.
BRICKLET_RS485_DEVICE_IDENTIFIER
¶This constant is used to identify a RS485 Bricklet.
The GetIdentity
function and the
TIPConnection.OnEnumerate
callback of the IP Connection have a deviceIdentifier
parameter to specify
the Brick's or Bricklet's type.
BRICKLET_RS485_DEVICE_DISPLAY_NAME
¶This constant represents the human readable name of a RS485 Bricklet.