Modbus - IO-16 Bricklet 2.0

This is the description of the Modbus protocol for the IO-16 Bricklet 2.0. General information and technical specifications for the IO-16 Bricklet 2.0 are summarized in its hardware description.

API

A general description of the Modbus protocol structure can be found here.

The Bricklet has sixteen channels that are named 0 to 15 in the API. The corresponding connectors on the Bricklet are labeled A0 to A7 for channel 0 to 7 and B0 to B7 for channels 8 to 15.

Basic Functions

BrickletIO16V2.set_value
Function ID:

1

Request:
  • value -- bool[16]
Response:

no response

Sets the output value of all sixteen channels. A value of true or false outputs logic 1 or logic 0 respectively on the corresponding channel.

Use set_selected_value to change only one output channel state.

For example: (True, True, False, False, ..., False) will turn the channels 0-1 high and the channels 2-15 low.

Note

This function does nothing for channels that are configured as input. Pull-up resistors can be switched on with set_configuration.

BrickletIO16V2.get_value
Function ID:

2

Request:

empty payload

Response:
  • value -- bool[16]

Returns the logic levels that are currently measured on the channels. This function works if the channel is configured as input as well as if it is configured as output.

BrickletIO16V2.set_selected_value
Function ID:

3

Request:
  • channel -- uint8
  • value -- bool
Response:

no response

Sets the output value of a specific channel without affecting the other channels.

Note

This function does nothing for channels that are configured as input. Pull-up resistors can be switched on with set_configuration.

BrickletIO16V2.set_configuration
Function ID:

4

Request:
  • channel -- uint8
  • direction -- char
  • value -- bool
Response:

no response

Configures the value and direction of a specific channel. Possible directions are 'i' and 'o' for input and output.

If the direction is configured as output, the value is either high or low (set as true or false).

If the direction is configured as input, the value is either pull-up or default (set as true or false).

For example:

  • (0, 'i', true) will set channel-0 as input pull-up.
  • (1, 'i', false) will set channel-1 as input default (floating if nothing is connected).
  • (2, 'o', true) will set channel-2 as output high.
  • (3, 'o', false) will set channel-3 as output low.

The default configuration is input with pull-up.

The following meanings are defined for the parameters of this function:

  • i: in, for direction
  • o: out, for direction

Advanced Functions

BrickletIO16V2.set_monoflop
Function ID:

10

Request:
  • channel -- uint8
  • value -- bool
  • time -- uint32
Response:

no response

Configures a monoflop of the specified channel.

The second parameter is the desired value of the specified channel. A true means relay closed and a false means relay open.

The third parameter indicates the time (in ms) that the channels should hold the value.

If this function is called with the parameters (0, 1, 1500) channel 0 will close and in 1.5s channel 0 will open again

A monoflop can be used as a fail-safe mechanism. For example: Lets assume you have a RS485 bus and a IO-16 Bricklet 2.0 connected to one of the slave stacks. You can now call this function every second, with a time parameter of two seconds and channel 0 closed. Channel 0 will be closed all the time. If now the RS485 connection is lost, then channel 0 will be opened in at most two seconds.

BrickletIO16V2.get_monoflop
Function ID:

11

Request:
  • channel -- uint8
Response:
  • value -- bool
  • time -- uint32
  • time_remaining -- uint32

Returns (for the given channel) the current value and the time as set by set_monoflop as well as the remaining time until the value flips.

If the timer is not running currently, the remaining time will be returned as 0.

BrickletIO16V2.get_edge_count
Function ID:

12

Request:
  • channel -- uint8
  • reset_counter -- bool
Response:
  • count -- uint32

Returns the current value of the edge counter for the selected channel. You can configure the edges that are counted with set_edge_count_configuration.

If you set the reset counter to true, the count is set back to 0 directly after it is read.

BrickletIO16V2.set_edge_count_configuration
Function ID:

13

Request:
  • channel -- uint8
  • edge_type -- uint8
  • debounce -- uint8
Response:

no response

Configures the edge counter for a specific channel.

The edge type parameter configures if rising edges, falling edges or both are counted if the channel is configured for input. Possible edge types are:

  • 0 = rising (default)
  • 1 = falling
  • 2 = both

The debounce time is given in ms.

Configuring an edge counter resets its value to 0.

If you don't know what any of this means, just leave it at default. The default configuration is very likely OK for you.

Default values: 0 (edge type) and 100ms (debounce time)

The following meanings are defined for the parameters of this function:

  • 0: rising, for edge_type
  • 1: falling, for edge_type
  • 2: both, for edge_type
BrickletIO16V2.get_edge_count_configuration
Function ID:

14

Request:
  • channel -- uint8
Response:
  • edge_type -- uint8
  • debounce -- uint8

Returns the edge type and debounce time for the selected channel as set by set_edge_count_configuration.

The following meanings are defined for the parameters of this function:

  • 0: rising, for edge_type
  • 1: falling, for edge_type
  • 2: both, for edge_type
BrickletIO16V2.get_spitfp_error_count
Function ID:

234

Request:

empty payload

Response:
  • error_count_ack_checksum -- uint32
  • error_count_message_checksum -- uint32
  • error_count_frame -- uint32
  • error_count_overflow -- uint32

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.

BrickletIO16V2.set_bootloader_mode
Function ID:

235

Request:
  • mode -- uint8
Response:
  • status -- uint8

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 meanings are defined for the parameters of this function:

  • 0: bootloader, for mode
  • 1: firmware, for mode
  • 2: bootloader wait for reboot, for mode
  • 3: firmware wait for reboot, for mode
  • 4: firmware wait for erase and reboot, for mode
  • 0: ok, for status
  • 1: invalid mode, for status
  • 2: no change, for status
  • 3: entry function not present, for status
  • 4: device identifier incorrect, for status
  • 5: crc mismatch, for status
BrickletIO16V2.get_bootloader_mode
Function ID:

236

Request:

empty payload

Response:
  • mode -- uint8

Returns the current bootloader mode, see set_bootloader_mode.

The following meanings are defined for the parameters of this function:

  • 0: bootloader, for mode
  • 1: firmware, for mode
  • 2: bootloader wait for reboot, for mode
  • 3: firmware wait for reboot, for mode
  • 4: firmware wait for erase and reboot, for mode
BrickletIO16V2.set_write_firmware_pointer
Function ID:

237

Request:
  • pointer -- uint32
Response:

no response

Sets the firmware pointer for 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.

BrickletIO16V2.write_firmware
Function ID:

238

Request:
  • data -- uint8[64]
Response:
  • status -- uint8

Writes 64 Bytes of firmware at the position as written by 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.

BrickletIO16V2.set_status_led_config
Function ID:

239

Request:
  • config -- uint8
Response:

no response

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 meanings are defined for the parameters of this function:

  • 0: off, for config
  • 1: on, for config
  • 2: show heartbeat, for config
  • 3: show status, for config
BrickletIO16V2.get_status_led_config
Function ID:

240

Request:

empty payload

Response:
  • config -- uint8

Returns the configuration as set by set_status_led_config

The following meanings are defined for the parameters of this function:

  • 0: off, for config
  • 1: on, for config
  • 2: show heartbeat, for config
  • 3: show status, for config
BrickletIO16V2.get_chip_temperature
Function ID:

242

Request:

empty payload

Response:
  • temperature -- int16

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.

BrickletIO16V2.reset
Function ID:243
Request:empty payload
Response:no response

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!

BrickletIO16V2.write_uid
Function ID:

248

Request:
  • uid -- uint32
Response:

no response

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.

BrickletIO16V2.read_uid
Function ID:

249

Request:

empty payload

Response:
  • uid -- uint32

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

BrickletIO16V2.get_identity
Function ID:

255

Request:

empty payload

Response:
  • uid -- char[8]
  • connected_uid -- char[8]
  • position -- char
  • hardware_version -- uint8[3]
  • firmware_version -- uint8[3]
  • device_identifier -- uint16

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 here

Callback Configuration Functions

BrickletIO16V2.get_configuration
Function ID:

5

Request:
  • channel -- uint8
Response:
  • direction -- char
  • value -- bool

Returns the channel configuration as set by set_configuration.

The following meanings are defined for the parameters of this function:

  • i: in, for direction
  • o: out, for direction
BrickletIO16V2.set_input_value_callback_configuration
Function ID:

6

Request:
  • channel -- uint8
  • period -- uint32
  • value_has_to_change -- bool
Response:

no response

This callback can be configured per channel.

The period in ms is the period with which the CALLBACK_INPUT_VALUE callback is triggered periodically. A value of 0 turns the callback off.

If the value has to change-parameter is set to true, the callback is only triggered after the value has changed. If the value didn't change within the period, the callback is triggered immediately on change.

If it is set to false, the callback is continuously triggered with the period, independent of the value.

The default value is (0, false).

BrickletIO16V2.get_input_value_callback_configuration
Function ID:

7

Request:
  • channel -- uint8
Response:
  • period -- uint32
  • value_has_to_change -- bool

Returns the callback configuration as set by set_input_value_callback_configuration.

BrickletIO16V2.set_all_input_value_callback_configuration
Function ID:

8

Request:
  • period -- uint32
  • value_has_to_change -- bool
Response:

no response

The period in ms is the period with which the CALLBACK_ALL_INPUT_VALUE callback is triggered periodically. A value of 0 turns the callback off.

If the value has to change-parameter is set to true, the callback is only triggered after the value has changed. If the value didn't change within the period, the callback is triggered immediately on change.

If it is set to false, the callback is continuously triggered with the period, independent of the value.

The default value is (0, false).

BrickletIO16V2.get_all_input_value_callback_configuration
Function ID:

9

Request:

empty payload

Response:
  • period -- uint32
  • value_has_to_change -- bool

Returns the callback configuration as set by set_all_input_value_callback_configuration.

Callbacks

BrickletIO16V2.CALLBACK_INPUT_VALUE
Function ID:

15

Response:
  • channel -- uint8
  • changed -- bool
  • value -- bool

This callback is triggered periodically according to the configuration set by set_input_value_callback_configuration.

The parameters are the channel, a value-changed indicator and the actual value for the channel. The changed parameter is true if the value has changed since the last callback.

BrickletIO16V2.CALLBACK_ALL_INPUT_VALUE
Function ID:

16

Response:
  • changed -- bool[16]
  • value -- bool[16]

This callback is triggered periodically according to the configuration set by set_all_input_value_callback_configuration.

The response values are the same as get_value. Additional the changed parameter is true if the value has changed since the last callback.

BrickletIO16V2.CALLBACK_MONOFLOP_DONE
Function ID:

17

Response:
  • channel -- uint8
  • value -- bool

This callback is triggered whenever a monoflop timer reaches 0. The response values contain the channel and the current value of the channel (the value after the monoflop).