NAME

Tinkerforge::BrickletRS485 - Communicates with RS485/Modbus devices with full- or half-duplex

CONSTANTS

DEVICE_IDENTIFIER

This constant is used to identify a RS485 Bricklet.

The get_identity() subroutine and the CALLBACK_ENUMERATE callback of the IP Connection have a device_identifier parameter to specify the Brick's or Bricklet's type.

DEVICE_DISPLAY_NAME

This constant represents the display name of a RS485 Bricklet.

CALLBACK_READ_LOW_LEVEL

This constant is used with the register_callback() subroutine to specify the CALLBACK_READ_LOW_LEVEL callback.

CALLBACK_ERROR_COUNT

This constant is used with the register_callback() subroutine to specify the CALLBACK_ERROR_COUNT callback.

CALLBACK_MODBUS_SLAVE_READ_COILS_REQUEST

This constant is used with the register_callback() subroutine to specify the CALLBACK_MODBUS_SLAVE_READ_COILS_REQUEST callback.

CALLBACK_MODBUS_MASTER_READ_COILS_RESPONSE_LOW_LEVEL

This constant is used with the register_callback() subroutine to specify the CALLBACK_MODBUS_MASTER_READ_COILS_RESPONSE_LOW_LEVEL callback.

CALLBACK_MODBUS_SLAVE_READ_HOLDING_REGISTERS_REQUEST

This constant is used with the register_callback() subroutine to specify the CALLBACK_MODBUS_SLAVE_READ_HOLDING_REGISTERS_REQUEST callback.

CALLBACK_MODBUS_MASTER_READ_HOLDING_REGISTERS_RESPONSE_LOW_LEVEL

This constant is used with the register_callback() subroutine to specify the CALLBACK_MODBUS_MASTER_READ_HOLDING_REGISTERS_RESPONSE_LOW_LEVEL callback.

CALLBACK_MODBUS_SLAVE_WRITE_SINGLE_COIL_REQUEST

This constant is used with the register_callback() subroutine to specify the CALLBACK_MODBUS_SLAVE_WRITE_SINGLE_COIL_REQUEST callback.

CALLBACK_MODBUS_MASTER_WRITE_SINGLE_COIL_RESPONSE

This constant is used with the register_callback() subroutine to specify the CALLBACK_MODBUS_MASTER_WRITE_SINGLE_COIL_RESPONSE callback.

CALLBACK_MODBUS_SLAVE_WRITE_SINGLE_REGISTER_REQUEST

This constant is used with the register_callback() subroutine to specify the CALLBACK_MODBUS_SLAVE_WRITE_SINGLE_REGISTER_REQUEST callback.

CALLBACK_MODBUS_MASTER_WRITE_SINGLE_REGISTER_RESPONSE

This constant is used with the register_callback() subroutine to specify the CALLBACK_MODBUS_MASTER_WRITE_SINGLE_REGISTER_RESPONSE callback.

CALLBACK_MODBUS_SLAVE_WRITE_MULTIPLE_COILS_REQUEST_LOW_LEVEL

This constant is used with the register_callback() subroutine to specify the CALLBACK_MODBUS_SLAVE_WRITE_MULTIPLE_COILS_REQUEST_LOW_LEVEL callback.

CALLBACK_MODBUS_MASTER_WRITE_MULTIPLE_COILS_RESPONSE

This constant is used with the register_callback() subroutine to specify the CALLBACK_MODBUS_MASTER_WRITE_MULTIPLE_COILS_RESPONSE callback.

CALLBACK_MODBUS_SLAVE_WRITE_MULTIPLE_REGISTERS_REQUEST_LOW_LEVEL

This constant is used with the register_callback() subroutine to specify the CALLBACK_MODBUS_SLAVE_WRITE_MULTIPLE_REGISTERS_REQUEST_LOW_LEVEL callback.

CALLBACK_MODBUS_MASTER_WRITE_MULTIPLE_REGISTERS_RESPONSE

This constant is used with the register_callback() subroutine to specify the CALLBACK_MODBUS_MASTER_WRITE_MULTIPLE_REGISTERS_RESPONSE callback.

CALLBACK_MODBUS_SLAVE_READ_DISCRETE_INPUTS_REQUEST

This constant is used with the register_callback() subroutine to specify the CALLBACK_MODBUS_SLAVE_READ_DISCRETE_INPUTS_REQUEST callback.

CALLBACK_MODBUS_MASTER_READ_DISCRETE_INPUTS_RESPONSE_LOW_LEVEL

This constant is used with the register_callback() subroutine to specify the CALLBACK_MODBUS_MASTER_READ_DISCRETE_INPUTS_RESPONSE_LOW_LEVEL callback.

CALLBACK_MODBUS_SLAVE_READ_INPUT_REGISTERS_REQUEST

This constant is used with the register_callback() subroutine to specify the CALLBACK_MODBUS_SLAVE_READ_INPUT_REGISTERS_REQUEST callback.

CALLBACK_MODBUS_MASTER_READ_INPUT_REGISTERS_RESPONSE_LOW_LEVEL

This constant is used with the register_callback() subroutine to specify the CALLBACK_MODBUS_MASTER_READ_INPUT_REGISTERS_RESPONSE_LOW_LEVEL callback.

CALLBACK_READ

This constant is used with the register_callback() subroutine to specify the CALLBACK_READ callback.

CALLBACK_MODBUS_MASTER_READ_COILS_RESPONSE

This constant is used with the register_callback() subroutine to specify the CALLBACK_MODBUS_MASTER_READ_COILS_RESPONSE callback.

CALLBACK_MODBUS_MASTER_READ_HOLDING_REGISTERS_RESPONSE

This constant is used with the register_callback() subroutine to specify the CALLBACK_MODBUS_MASTER_READ_HOLDING_REGISTERS_RESPONSE callback.

CALLBACK_MODBUS_SLAVE_WRITE_MULTIPLE_COILS_REQUEST

This constant is used with the register_callback() subroutine to specify the CALLBACK_MODBUS_SLAVE_WRITE_MULTIPLE_COILS_REQUEST callback.

CALLBACK_MODBUS_SLAVE_WRITE_MULTIPLE_REGISTERS_REQUEST

This constant is used with the register_callback() subroutine to specify the CALLBACK_MODBUS_SLAVE_WRITE_MULTIPLE_REGISTERS_REQUEST callback.

CALLBACK_MODBUS_MASTER_READ_DISCRETE_INPUTS_RESPONSE

This constant is used with the register_callback() subroutine to specify the CALLBACK_MODBUS_MASTER_READ_DISCRETE_INPUTS_RESPONSE callback.

CALLBACK_MODBUS_MASTER_READ_INPUT_REGISTERS_RESPONSE

This constant is used with the register_callback() subroutine to specify the CALLBACK_MODBUS_MASTER_READ_INPUT_REGISTERS_RESPONSE callback.

FUNCTION_WRITE_LOW_LEVEL

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTION_READ_LOW_LEVEL

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTION_ENABLE_READ_CALLBACK

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTION_DISABLE_READ_CALLBACK

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTION_IS_READ_CALLBACK_ENABLED

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTION_SET_RS485_CONFIGURATION

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTION_GET_RS485_CONFIGURATION

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTION_SET_MODBUS_CONFIGURATION

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTION_GET_MODBUS_CONFIGURATION

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTION_SET_MODE

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTION_GET_MODE

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTION_SET_COMMUNICATION_LED_CONFIG

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTION_GET_COMMUNICATION_LED_CONFIG

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTION_SET_ERROR_LED_CONFIG

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTION_GET_ERROR_LED_CONFIG

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTION_SET_BUFFER_CONFIG

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTION_GET_BUFFER_CONFIG

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTION_GET_BUFFER_STATUS

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTION_ENABLE_ERROR_COUNT_CALLBACK

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTION_DISABLE_ERROR_COUNT_CALLBACK

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTION_IS_ERROR_COUNT_CALLBACK_ENABLED

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTION_GET_ERROR_COUNT

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTION_GET_MODBUS_COMMON_ERROR_COUNT

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTION_MODBUS_SLAVE_REPORT_EXCEPTION

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTION_MODBUS_SLAVE_ANSWER_READ_COILS_REQUEST_LOW_LEVEL

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTION_MODBUS_MASTER_READ_COILS

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTION_MODBUS_SLAVE_ANSWER_READ_HOLDING_REGISTERS_REQUEST_LOW_LEVEL

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTION_MODBUS_MASTER_READ_HOLDING_REGISTERS

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTION_MODBUS_SLAVE_ANSWER_WRITE_SINGLE_COIL_REQUEST

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTION_MODBUS_MASTER_WRITE_SINGLE_COIL

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTION_MODBUS_SLAVE_ANSWER_WRITE_SINGLE_REGISTER_REQUEST

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTION_MODBUS_MASTER_WRITE_SINGLE_REGISTER

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTION_MODBUS_SLAVE_ANSWER_WRITE_MULTIPLE_COILS_REQUEST

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTION_MODBUS_MASTER_WRITE_MULTIPLE_COILS_LOW_LEVEL

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTION_MODBUS_SLAVE_ANSWER_WRITE_MULTIPLE_REGISTERS_REQUEST

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTION_MODBUS_MASTER_WRITE_MULTIPLE_REGISTERS_LOW_LEVEL

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTION_MODBUS_SLAVE_ANSWER_READ_DISCRETE_INPUTS_REQUEST_LOW_LEVEL

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTION_MODBUS_MASTER_READ_DISCRETE_INPUTS

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTION_MODBUS_SLAVE_ANSWER_READ_INPUT_REGISTERS_REQUEST_LOW_LEVEL

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTION_MODBUS_MASTER_READ_INPUT_REGISTERS

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTION_GET_SPITFP_ERROR_COUNT

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTION_SET_BOOTLOADER_MODE

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTION_GET_BOOTLOADER_MODE

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTION_SET_WRITE_FIRMWARE_POINTER

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTION_WRITE_FIRMWARE

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTION_SET_STATUS_LED_CONFIG

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTION_GET_STATUS_LED_CONFIG

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTION_GET_CHIP_TEMPERATURE

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTION_RESET

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTION_WRITE_UID

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTION_READ_UID

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTION_GET_IDENTITY

This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.

FUNCTIONS

new()

Creates an object with the unique device ID *uid* and adds it to the IP Connection *ipcon*.

write_low_level()

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 :func:`Set RS485 Configuration` for configuration possibilities regarding baudrate, parity and so on.

read_low_level()

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 :func:`Enable Read Callback` and :cb:`Read` callback.

enable_read_callback()

Enables the :cb:`Read` callback.

By default the callback is disabled.

disable_read_callback()

Disables the :cb:`Read` callback.

By default the callback is disabled.

is_read_callback_enabled()

Returns *true* if the :cb:`Read` callback is enabled, *false* otherwise.

set_rs485_configuration()

Sets the configuration for the RS485 communication. Available options:

* Baudrate between 100 and 2000000 baud. * Parity of none, odd or even. * Stopbits can be 1 or 2. * Word length of 5 to 8. * Half- or Full-Duplex.

The default is: 115200 baud, parity none, 1 stop bit, word length 8, half duplex.

get_rs485_configuration()

Returns the configuration as set by :func:`Set RS485 Configuration`.

set_modbus_configuration()

Sets the configuration for the RS485 Modbus communication. Available options:

* Slave Address: Address to be used as the Modbus slave address in Modbus slave mode. Valid Modbus slave address range is 1 to 247. * Master Request Timeout: Specifies how long the master should wait for a response from a slave in milliseconds when in Modbus master mode.

The default is: Slave Address = 1 and Master Request Timeout = 1000 milliseconds (1 second).

get_modbus_configuration()

Returns the configuration as set by :func:`Set Modbus Configuration`.

set_mode()

Sets the mode of the Bricklet in which it operates. Available options are

* RS485, * Modbus Master RTU and * Modbus Slave RTU.

The default is: RS485 mode.

get_mode()

Returns the configuration as set by :func:`Set Mode`.

set_communication_led_config()

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.

get_communication_led_config()

Returns the configuration as set by :func:`Set Communication LED Config`

set_error_led_config()

Sets the error LED configuration.

By default the error LED turns on if there is any error (see :cb:`Error Count` 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.

get_error_led_config()

Returns the configuration as set by :func:`Set Error LED Config`.

set_buffer_config()

Sets the send and receive buffer size in byte. In sum there is 10240 byte (10kb) buffer available and the minimum buffer size is 1024 byte (1kb) for both.

The current buffer content is lost if this function is called.

The send buffer holds data that was given by :func:`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 :func:`Read` or through :cb:`Read` callback.

The default configuration is 5120 byte (5kb) per buffer.

get_buffer_config()

Returns the buffer configuration as set by :func:`Set Buffer Config`.

get_buffer_status()

Returns the currently used bytes for the send and received buffer.

See :func:`Set Buffer Config` for buffer size configuration.

enable_error_count_callback()

Enables the :cb:`Error Count` callback.

By default the callback is disabled.

disable_error_count_callback()

Disables the :cb:`Error Count` callback.

By default the callback is disabled.

is_error_count_callback_enabled()

Returns *true* if the :cb:`Error Count` callback is enabled, *false* otherwise.

get_error_count()

Returns the current number of overrun and parity errors.

get_modbus_common_error_count()

Returns the current number of errors occurred in Modbus mode.

* Timeout Error Count: Number of timeouts occurred. * Checksum Error Count: Number of failures due to Modbus frame CRC16 checksum mismatch. * Frame Too Big Error Count: Number of times frames were rejected because they exceeded maximum Modbus frame size which is 256 bytes. * Illegal Function Error Count: Number of errors when an unimplemented or illegal function is requested. This corresponds to Modbus exception code 1. * Illegal Data Address Error Count: Number of errors due to invalid data address. This corresponds to Modbus exception code 2. * Illegal Data Value Error Count: Number of errors due to invalid data value. This corresponds to Modbus exception code 3. * Slave Device Failure Error Count: Number of errors occurred on the slave device which were unrecoverable. This corresponds to Modbus exception code 4.

modbus_slave_report_exception()

In Modbus slave mode this function can be used to report a Modbus exception for a Modbus master request.

* Request ID: Request ID of the request received by the slave. * Exception Code: Modbus exception code to report to the Modbus master.

modbus_slave_answer_read_coils_request_low_level()

In Modbus slave mode this function can be used to answer a master request to read coils.

* Request ID: Request ID of the corresponding request that is being answered. * Coils: Data that is to be sent to the Modbus master for the corresponding request.

This function must be called from the :cb:`Modbus Slave Read Coils Request` callback with the Request ID as provided by the argument of the callback.

modbus_master_read_coils()

In Modbus master mode this function can be used to read coils from a slave. This function creates a Modbus function code 1 request.

* Slave Address: Address of the target Modbus slave. * Starting Address: Starting address of the read. * Count: Number of coils to read.

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 :cb:`Modbus Master Read Coils Response` 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.

modbus_slave_answer_read_holding_registers_request_low_level()

In Modbus slave mode this function can be used to answer a master request to read holding registers.

* Request ID: Request ID of the corresponding request that is being answered. * Holding Registers: Data that is to be sent to the Modbus master for the corresponding request.

This function must be called from the :cb:`Modbus Slave Read Holding Registers Request` callback with the Request ID as provided by the argument of the callback.

modbus_master_read_holding_registers()

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.

* Slave Address: Address of the target Modbus slave. * Starting Address: Starting address of the read. * Count: Number of holding registers to read.

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 :cb:`Modbus Master Read Holding Registers Response` 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.

modbus_slave_answer_write_single_coil_request()

In Modbus slave mode this function can be used to answer a master request to write a single coil.

* Request ID: Request ID of the corresponding request that is being answered.

This function must be called from the :cb:`Modbus Slave Write Single Coil Request` callback with the Request ID as provided by the arguments of the callback.

modbus_master_write_single_coil()

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.

* Slave Address: Address of the target Modbus slave. * Coil Address: Address of the coil. * Coil Value: Value to be written.

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 :cb:`Modbus Master Write Single Coil Response` 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.

modbus_slave_answer_write_single_register_request()

In Modbus slave mode this function can be used to answer a master request to write a single register.

* Request ID: Request ID of the corresponding request that is being answered.

This function must be called from the :cb:`Modbus Slave Write Single Register Request` callback with the Request ID, Register Address and Register Value as provided by the arguments of the callback.

modbus_master_write_single_register()

In Modbus master mode this function can be used to write a single register of a slave. This function creates a Modbus function code 6 request.

* Slave Address: Address of the target Modbus slave. * Register Address: Address of the register. * Register Value: Value to be written.

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 :cb:`Modbus Master Write Single Register Response` 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.

modbus_slave_answer_write_multiple_coils_request()

In Modbus slave mode this function can be used to answer a master request to write multiple coils.

* Request ID: Request ID of the corresponding request that is being answered.

This function must be called from the :cb:`Modbus Slave Write Multiple Coils Request` callback with the Request ID of the callback.

modbus_master_write_multiple_coils_low_level()

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.

* Slave Address: Address of the target Modbus slave. * Starting Address: Starting address of the write.

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 :cb:`Modbus Master Write Multiple Coils Response` 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.

modbus_slave_answer_write_multiple_registers_request()

In Modbus slave mode this function can be used to answer a master request to write multiple registers.

* Request ID: Request ID of the corresponding request that is being answered.

This function must be called from the :cb:`Modbus Slave Write Multiple Registers Request` callback with the Request ID of the callback.

modbus_master_write_multiple_registers_low_level()

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.

* Slave Address: Address of the target Modbus slave. * Starting Address: Starting Address of the write.

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 :cb:`Modbus Master Write Multiple Registers Response` 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.

modbus_slave_answer_read_discrete_inputs_request_low_level()

In Modbus slave mode this function can be used to answer a master request to read discrete inputs.

* Request ID: Request ID of the corresponding request that is being answered. * Discrete Inputs: Data that is to be sent to the Modbus master for the corresponding request.

This function must be called from the :cb:`Modbus Slave Read Discrete Inputs Request` callback with the Request ID as provided by the argument of the callback.

modbus_master_read_discrete_inputs()

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.

* Slave Address: Address of the target Modbus slave. * Starting Address: Starting address of the read. * Count: Number of discrete inputs to read.

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 :cb:`Modbus Master Read Discrete Inputs Response` 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.

modbus_slave_answer_read_input_registers_request_low_level()

In Modbus slave mode this function can be used to answer a master request to read input registers.

* Request ID: Request ID of the corresponding request that is being answered. * Input Registers: Data that is to be sent to the Modbus master for the corresponding request.

This function must be called from the :cb:`Modbus Slave Read Input Registers Request` callback with the Request ID as provided by the argument of the callback.

modbus_master_read_input_registers()

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.

* Slave Address: Address of the target Modbus slave. * Starting Address: Starting address of the read. * Count: Number of input registers to read.

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 :cb:`Modbus Master Read Input Registers Response` 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.

get_spitfp_error_count()

Returns the error count for the communication between Brick and Bricklet.

The errors are divided into

* ACK checksum errors, * message checksum errors, * framing errors and * overflow errors.

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.

set_bootloader_mode()

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.

get_bootloader_mode()

Returns the current bootloader mode, see :func:`Set Bootloader Mode`.

set_write_firmware_pointer()

Sets the firmware pointer for :func:`Write Firmware`. 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.

write_firmware()

Writes 64 Bytes of firmware at the position as written by :func:`Set Write Firmware Pointer` 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.

set_status_led_config()

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.

get_status_led_config()

Returns the configuration as set by :func:`Set Status LED Config`

get_chip_temperature()

Returns the temperature in °C 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.

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!

write_uid()

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.

read_uid()

Returns the current UID as an integer. Encode as Base58 to get the usual string version.

get_identity()

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' or 'd'.

The device identifier numbers can be found :ref:`here <device_identifier>`. |device_identifier_constant|

write()

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 :func:`Set RS485 Configuration` for configuration possibilities regarding baudrate, parity and so on.

read()

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 :func:`Enable Read Callback` and :cb:`Read` callback.

modbus_slave_answer_read_coils_request()

In Modbus slave mode this function can be used to answer a master request to read coils.

* Request ID: Request ID of the corresponding request that is being answered. * Coils: Data that is to be sent to the Modbus master for the corresponding request.

This function must be called from the :cb:`Modbus Slave Read Coils Request` callback with the Request ID as provided by the argument of the callback.

modbus_slave_answer_read_holding_registers_request()

In Modbus slave mode this function can be used to answer a master request to read holding registers.

* Request ID: Request ID of the corresponding request that is being answered. * Holding Registers: Data that is to be sent to the Modbus master for the corresponding request.

This function must be called from the :cb:`Modbus Slave Read Holding Registers Request` callback with the Request ID as provided by the argument of the callback.

modbus_master_write_multiple_coils()

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.

* Slave Address: Address of the target Modbus slave. * Starting Address: Starting address of the write.

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 :cb:`Modbus Master Write Multiple Coils Response` 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.

modbus_master_write_multiple_registers()

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.

* Slave Address: Address of the target Modbus slave. * Starting Address: Starting Address of the write.

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 :cb:`Modbus Master Write Multiple Registers Response` 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.

modbus_slave_answer_read_discrete_inputs_request()

In Modbus slave mode this function can be used to answer a master request to read discrete inputs.

* Request ID: Request ID of the corresponding request that is being answered. * Discrete Inputs: Data that is to be sent to the Modbus master for the corresponding request.

This function must be called from the :cb:`Modbus Slave Read Discrete Inputs Request` callback with the Request ID as provided by the argument of the callback.

modbus_slave_answer_read_input_registers_request()

In Modbus slave mode this function can be used to answer a master request to read input registers.

* Request ID: Request ID of the corresponding request that is being answered. * Input Registers: Data that is to be sent to the Modbus master for the corresponding request.

This function must be called from the :cb:`Modbus Slave Read Input Registers Request` callback with the Request ID as provided by the argument of the callback.