Modbus - Piezo Speaker Bricklet 2.0¶

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

API¶

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

Basic Functions¶

BrickletPiezoSpeakerV2.set_beep¶

Function ID:	1
Request:	frequency – Type: uint16, Unit: 1 Hz, Range: [50 to 15000] volume – Type: uint8, Range: [0 to 10] duration – Type: uint32, Unit: 1 ms, Range: [0 to 2³² - 1] with meanings
Response:	no response

Beeps with the given frequency and volume for the duration.

A duration of 0 stops the current beep if any is ongoing. A duration of 4294967295 results in an infinite beep.

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

For duration:

0 = Off
4294967295 = Infinite

BrickletPiezoSpeakerV2.get_beep¶

Function ID:	2
Request:	empty payload
Response:	frequency – Type: uint16, Unit: 1 Hz, Range: [50 to 15000] volume – Type: uint8, Range: [0 to 10] duration – Type: uint32, Unit: 1 ms, Range: [0 to 2³² - 1] with meanings duration_remaining – Type: uint32, Unit: 1 ms, Range: [0 to 2³² - 1]

Returns the last beep settings as set by set_beep. If a beep is currently running it also returns the remaining duration of the beep.

If the frequency or volume is updated during a beep (with update_frequency or update_volume) this function returns the updated value.

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

For duration:

0 = Off
4294967295 = Infinite

BrickletPiezoSpeakerV2.set_alarm¶

Function ID:	3
Request:	start_frequency – Type: uint16, Unit: 1 Hz, Range: [50 to 14999] end_frequency – Type: uint16, Unit: 1 Hz, Range: [51 to 15000] step_size – Type: uint16, Unit: 1 Hz, Range: [0 to 14950] step_delay – Type: uint16, Unit: 1 ms, Range: [0 to 2¹⁶ - 1] volume – Type: uint8, Range: [0 to 10] duration – Type: uint32, Unit: 1 ms, Range: [0 to 2³² - 1] with meanings
Response:	no response

Creates an alarm (a tone that goes back and force between two specified frequencies).

The following parameters can be set:

Start Frequency: Start frequency of the alarm.
End Frequency: End frequency of the alarm.
Step Size: Size of one step of the sweep between the start/end frequencies.
Step Delay: Delay between two steps (duration of time that one tone is used in a sweep).
Duration: Duration of the alarm.

A duration of 0 stops the current alarm if any is ongoing. A duration of 4294967295 results in an infinite alarm.

Below you can find two sets of example settings that you can try out. You can use these as a starting point to find an alarm signal that suits your application.

Example 1: 10 seconds of loud annoying fast alarm

Start Frequency = 800
End Frequency = 2000
Step Size = 10
Step Delay = 1
Volume = 10
Duration = 10000

Example 2: 10 seconds of soft siren sound with slow build-up

Start Frequency = 250
End Frequency = 750
Step Size = 1
Step Delay = 5
Volume = 0
Duration = 10000

The following conditions must be met:

Start Frequency: has to be smaller than end frequency
End Frequency: has to be bigger than start frequency
Step Size: has to be small enough to fit into the frequency range
Step Delay: has to be small enough to fit into the duration

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

For duration:

0 = Off
4294967295 = Infinite

BrickletPiezoSpeakerV2.get_alarm¶

Function ID:	4
Request:	empty payload
Response:	start_frequency – Type: uint16, Unit: 1 Hz, Range: [50 to 14999] end_frequency – Type: uint16, Unit: 1 Hz, Range: [51 to 15000] step_size – Type: uint16, Unit: 1 Hz, Range: [50 to 14950] step_delay – Type: uint16, Unit: 1 ms, Range: [0 to 2¹⁶ - 1] volume – Type: uint8, Range: [0 to 10] duration – Type: uint32, Unit: 1 ms, Range: [0 to 2³² - 1] with meanings duration_remaining – Type: uint32, Unit: 1 ms, Range: [0 to 2³² - 1] with meanings current_frequency – Type: uint16, Unit: 1 Hz, Range: [50 to 15000]

Returns the last alarm settings as set by set_alarm. If an alarm is currently running it also returns the remaining duration of the alarm as well as the current frequency of the alarm.

If the volume is updated during an alarm (with update_volume) this function returns the updated value.

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

For duration:

0 = Off
4294967295 = Infinite

For duration_remaining:

0 = Off
4294967295 = Infinite

BrickletPiezoSpeakerV2.update_volume¶

Function ID:	5
Request:	volume – Type: uint8, Range: [0 to 10]
Response:	no response

Updates the volume of an ongoing beep or alarm.

BrickletPiezoSpeakerV2.update_frequency¶

Function ID:	6
Request:	frequency – Type: uint16, Unit: 1 Hz, Range: [50 to 15000]
Response:	no response

Updates the frequency of an ongoing beep.

Advanced Functions¶

BrickletPiezoSpeakerV2.get_spitfp_error_count¶

Function ID:	234
Request:	empty payload
Response:	error_count_ack_checksum – Type: uint32, Range: [0 to 2³² - 1] error_count_message_checksum – Type: uint32, Range: [0 to 2³² - 1] error_count_frame – Type: uint32, Range: [0 to 2³² - 1] error_count_overflow – Type: uint32, Range: [0 to 2³² - 1]

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.

BrickletPiezoSpeakerV2.set_status_led_config¶

Function ID:	239
Request:	config – Type: uint8, Range: See meanings, Default: 3
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 elements of this function:

For config:

0 = Off
1 = On
2 = Show Heartbeat
3 = Show Status

BrickletPiezoSpeakerV2.get_status_led_config¶

Function ID:	240
Request:	empty payload
Response:	config – Type: uint8, Range: See meanings, Default: 3

Returns the configuration as set by set_status_led_config

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

For config:

0 = Off
1 = On
2 = Show Heartbeat
3 = Show Status

BrickletPiezoSpeakerV2.get_chip_temperature¶

Function ID:	242
Request:	empty payload
Response:	temperature – Type: int16, Unit: 1 °C, Range: [-2¹⁵ to 2¹⁵ - 1]

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.

BrickletPiezoSpeakerV2.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!

BrickletPiezoSpeakerV2.get_identity¶

Function ID:	255
Request:	empty payload
Response:	uid – Type: char[8] connected_uid – Type: char[8] position – Type: char, Range: ['a' to 'h', 'z'] hardware_version – Type: uint8[3] 0: major – Type: uint8, Range: [0 to 255] 1: minor – Type: uint8, Range: [0 to 255] 2: revision – Type: uint8, Range: [0 to 255] firmware_version – Type: uint8[3] 0: major – Type: uint8, Range: [0 to 255] 1: minor – Type: uint8, Range: [0 to 255] 2: revision – Type: uint8, Range: [0 to 255] device_identifier – Type: uint16, Range: [0 to 2¹⁶ - 1]

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.

Callbacks¶

BrickletPiezoSpeakerV2.CALLBACK_BEEP_FINISHED¶

Function ID:	7
Response:	empty payload

This callback is triggered if a beep set by set_beep is finished

BrickletPiezoSpeakerV2.CALLBACK_ALARM_FINISHED¶

Function ID:	8
Response:	empty payload

This callback is triggered if a alarm set by set_alarm is finished

Internal Functions¶

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.

BrickletPiezoSpeakerV2.set_bootloader_mode¶

Function ID:	235
Request:	mode – Type: uint8, Range: See meanings
Response:	status – Type: uint8, Range: See meanings

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 elements of this function:

For mode:

0 = Bootloader
1 = Firmware
2 = Bootloader Wait For Reboot
3 = Firmware Wait For Reboot
4 = Firmware Wait For Erase And Reboot

For status:

0 = OK
1 = Invalid Mode
2 = No Change
3 = Entry Function Not Present
4 = Device Identifier Incorrect
5 = CRC Mismatch

BrickletPiezoSpeakerV2.get_bootloader_mode¶

Function ID:	236
Request:	empty payload
Response:	mode – Type: uint8, Range: See meanings

Returns the current bootloader mode, see set_bootloader_mode.

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

For mode:

0 = Bootloader
1 = Firmware
2 = Bootloader Wait For Reboot
3 = Firmware Wait For Reboot
4 = Firmware Wait For Erase And Reboot

BrickletPiezoSpeakerV2.set_write_firmware_pointer¶

Function ID:	237
Request:	pointer – Type: uint32, Unit: 1 B, Range: [0 to 2³² - 1]
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.

BrickletPiezoSpeakerV2.write_firmware¶

Function ID:	238
Request:	data – Type: uint8[64], Range: [0 to 255]
Response:	status – Type: uint8, Range: [0 to 255]

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.

BrickletPiezoSpeakerV2.write_uid¶

Function ID:	248
Request:	uid – Type: uint32, Range: [0 to 2³² - 1]
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.

BrickletPiezoSpeakerV2.read_uid¶

Function ID:	249
Request:	empty payload
Response:	uid – Type: uint32, Range: [0 to 2³² - 1]

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