# Python library The `Spectral-BLDC` package ([Spectral-BLDC-Python](https://github.com/Source-Robotics/Spectral-BLDC-Python), `pip install Spectral-BLDC`) has one method per CAN message in `Spectral_BLDC.SpectralCAN`, and `Spectral_BLDC.CanCommunication` for the bus. [With Python](https://docs.source-robotics.com/STEPFOC-docs/110/06-operation/python/) shows how they are used. ## Calls and messages
| Library call | Sends | Answered with | |---|---|---| | `Send_data_pack_1()` | [Send_data_pack_1](https://docs.source-robotics.com/STEPFOC-docs/110/reference/can/motion/#send_data_pack_1) (ID 2)
Motion | Respond_data_pack_1 | | `Send_data_pack_PD()` | [Send_data_pack_PD](https://docs.source-robotics.com/STEPFOC-docs/110/reference/can/motion/#send_data_pack_pd) (ID 4)
Motion | Respond_data_pack_1 | | `Send_data_pack_HALL()` | [Send_data_pack_HALL](https://docs.source-robotics.com/STEPFOC-docs/110/reference/can/motion/#send_data_pack_hall) (ID 31)
Motion | Respond_data_hall | | `Send_PD_Gains()` | [Send_PD_Gains](https://docs.source-robotics.com/STEPFOC-docs/110/reference/can/gains-and-limits/#send_pd_gains) (ID 16)
Gains and limits | — | | `Send_Current_Gains()` | [Send_Current_Gains](https://docs.source-robotics.com/STEPFOC-docs/110/reference/can/gains-and-limits/#send_current_gains) (ID 17)
Gains and limits | — | | `Send_Velocity_Gains()` | [Send_Velocity_Gains](https://docs.source-robotics.com/STEPFOC-docs/110/reference/can/gains-and-limits/#send_velocity_gains) (ID 18)
Gains and limits | — | | `Send_Position_Gains()` | [Send_Position_Gains](https://docs.source-robotics.com/STEPFOC-docs/110/reference/can/gains-and-limits/#send_position_gains) (ID 19)
Gains and limits | — | | `Send_Limits()` | [Send_Limits](https://docs.source-robotics.com/STEPFOC-docs/110/reference/can/gains-and-limits/#send_limits) (ID 20)
Gains and limits | — | | `Send_Kt()` | [Send_Kt](https://docs.source-robotics.com/STEPFOC-docs/110/reference/can/gains-and-limits/#send_kt) (ID 22)
Gains and limits | — | | `Send_Voltage_Limit()` | [Send_Voltage_Limit](https://docs.source-robotics.com/STEPFOC-docs/110/reference/can/gains-and-limits/#send_voltage_limit) (ID 34)
Gains and limits | — | | `Send_Respond_Ping()` | [Send_Respond_Ping](https://docs.source-robotics.com/STEPFOC-docs/110/reference/can/status/#send_respond_ping) (ID 10)
Status requests | Send_Respond_Ping (data frame) | | `Send_Respond_Temperature()` | [Send_Respond_Temperature](https://docs.source-robotics.com/STEPFOC-docs/110/reference/can/status/#send_respond_temperature) (ID 23)
Status requests | Send_Respond_Temperature (data frame) | | `Send_Respond_Voltage()` | [Send_Respond_Voltage](https://docs.source-robotics.com/STEPFOC-docs/110/reference/can/status/#send_respond_voltage) (ID 24)
Status requests | Send_Respond_Voltage (data frame) | | `Send_Respond_Device_Info()` | [Send_Respond_Device_Info](https://docs.source-robotics.com/STEPFOC-docs/110/reference/can/status/#send_respond_device_info) (ID 25)
Status requests | Send_Respond_Device_Info (data frame) | | `Send_Respond_State_of_Errors()` | [Send_Respond_State_of_Errors](https://docs.source-robotics.com/STEPFOC-docs/110/reference/can/status/#send_respond_state_of_errors) (ID 26)
Status requests | Send_Respond_State_of_Errors (data frame) | | `Send_Respond_Iq_data()` | [Send_Respond_Iq_data](https://docs.source-robotics.com/STEPFOC-docs/110/reference/can/status/#send_respond_iq_data) (ID 27)
Status requests | Send_Respond_Iq_data (data frame) | | `Send_Respond_Encoder_data()` | [Send_Respond_Encoder_data](https://docs.source-robotics.com/STEPFOC-docs/110/reference/can/status/#send_respond_encoder_data) (ID 28)
Status requests | Send_Respond_Encoder_data (data frame) | | `Send_Respond_Kt()` | [Send_Respond_Kt](https://docs.source-robotics.com/STEPFOC-docs/110/reference/can/status/#send_respond_kt) (ID 33)
Status requests | Send_Respond_Kt (data frame) | | `Send_Respond_Identity()` | [Send_Respond_Identity](https://docs.source-robotics.com/STEPFOC-docs/110/reference/can/status/#send_respond_identity) (ID 39)
Status requests | Send_Respond_Identity (data frame) | | `Send_Respond_Telemetry()` | [Send_Respond_Telemetry](https://docs.source-robotics.com/STEPFOC-docs/110/reference/can/status/#send_respond_telemetry) (ID 40)
Status requests | Send_Respond_Telemetry (data frame) | | `Send_CAN_ID()` | [Send_CAN_ID](https://docs.source-robotics.com/STEPFOC-docs/110/reference/can/system/#send_can_id) (ID 11)
System | — | | `Send_ESTOP()` | [Send_ESTOP](https://docs.source-robotics.com/STEPFOC-docs/110/reference/can/system/#send_estop) (ID 0)
System | — | | `Send_Idle()` | [Send_Idle](https://docs.source-robotics.com/STEPFOC-docs/110/reference/can/system/#send_idle) (ID 12)
System | — | | `Send_Save_config()` | [Send_Save_config](https://docs.source-robotics.com/STEPFOC-docs/110/reference/can/system/#send_save_config) (ID 13)
System | — | | `Send_Reset()` | [Send_Reset](https://docs.source-robotics.com/STEPFOC-docs/110/reference/can/system/#send_reset) (ID 14)
System | — | | `Send_Clear_Error()` | [Send_Clear_Error](https://docs.source-robotics.com/STEPFOC-docs/110/reference/can/system/#send_clear_error) (ID 1)
System | — | | `Send_Watchdog()` | [Send_Watchdog](https://docs.source-robotics.com/STEPFOC-docs/110/reference/can/system/#send_watchdog) (ID 15)
System | — | | `Send_Heartbeat_Setup()` | [Send_Heartbeat_Setup](https://docs.source-robotics.com/STEPFOC-docs/110/reference/can/system/#send_heartbeat_setup) (ID 30)
System | — | | `Send_Parameter()` | [Send_Parameter](https://docs.source-robotics.com/STEPFOC-docs/110/reference/can/parameters/#send_parameter) (ID 36)
Parameters and buffers | — | | `Send_Get_Parameter()` | [Send_Get_Parameter](https://docs.source-robotics.com/STEPFOC-docs/110/reference/can/parameters/#send_get_parameter) (ID 37)
Parameters and buffers | Respond_Parameter | | `Send_Buffer_Read()` | [Send_Buffer_Read](https://docs.source-robotics.com/STEPFOC-docs/110/reference/can/parameters/#send_buffer_read) (ID 41)
Parameters and buffers | — | | `Send_Cogging_Harmonic(), Send_Cogging_Table()` | [Send_Buffer_Write](https://docs.source-robotics.com/STEPFOC-docs/110/reference/can/parameters/#send_buffer_write) (ID 43)
Parameters and buffers | — | | `Send_Sound()` | [Send_Sound](https://docs.source-robotics.com/STEPFOC-docs/110/reference/can/sound/#send_sound) (ID 44)
Sound | — | | `Send_Samples()` | [Send_Sound_Samples](https://docs.source-robotics.com/STEPFOC-docs/110/reference/can/sound/#send_sound_samples) (ID 45)
Sound | — | | `Send_gripper_data_pack()` | [Send_gripper_data_pack](https://docs.source-robotics.com/STEPFOC-docs/110/reference/can/gripper/#send_gripper_data_pack) (ID 61)
Gripper | Respond_Gripper_data_pack | | `Send_gripper_calibrate()` | [Send_gripper_calibrate](https://docs.source-robotics.com/STEPFOC-docs/110/reference/can/gripper/#send_gripper_calibrate) (ID 62)
Gripper | — |
The calls for the messages added in firmware 109 (Send_Parameter, Send_Get_Parameter, Send_Respond_Identity, Send_Respond_Telemetry, Send_Buffer_Read, Send_Cogging_Harmonic, Send_Cogging_Table, Send_Sound, Send_Samples), and the actions 'Coast' and 'Descend' of Send_Watchdog, come with library 1.21. It also adds calls built on the parameters, among them Send_Watchdog_Fallback, Send_Tool_ID, Send_Cogging_Mode, Send_Capture_Setup, Send_Capture_Trigger, Send_Histogram, Send_Cogging_Calibrate and Send_Encoder_Calibrate; the sound calls Send_Tone, Send_Sound_Stop, Send_Sound_Event, Send_Sound_Play, Send_Sound_Clear, Send_Samples_Play and Send_Samples_Stop on top of Send_Sound and Send_Samples; and the module `Spectral_BLDC.music` (note names, ringtone melodies, MIDI and WAV files as queue events and samples, see [Sound](https://docs.source-robotics.com/STEPFOC-docs/110/06-operation/sound/)). The same release adds `Spectral_BLDC.helpers`, blocking functions that send a request and wait for the answer: `get_parameter` and `set_parameter` (which reads the value back), `read_identity`, `read_telemetry`, `features`, `read_buffer`, `capture`, `wait_for_state` (for the encoder table, the anti-cogging and other runs), and `play_events` and `stream_samples` for sound. They are for setting up and diagnostics, not for the inside of a fast control loop. The library's `examples` folder shows them at work: `parameters_and_status.py`, `capture.py`, `calibration_features.py`, `watchdog.py` and `sound.py`. The same release is stricter about what it sends and reads: - `Send_Parameter` takes the value itself. Parameters 8 to 16 and 20 are sent as floats (`Send_Parameter(16, 1500)` is 1500 mA); every other parameter takes a whole number, and anything else raises `ValueError`. - A position or a speed that does not fit 24 bits, or a current that does not fit 16 bits, raises `ValueError`; 1.20 wrapped it round. `Send_Voltage_Limit` raises `ValueError` outside 0 to 60000 mV. - A node ID must be 0 to 15. - `UnpackData` ignores frames from other nodes, remote frames and extended frames. - Parameters 79, 80 and 84 to 87 read as unsigned numbers. - A send that fails returns `False` and is logged once. ## Receiving `CanCommunication.receive_can_messages(timeout)` returns `(message, ids)`: the raw `python-can` message and a tuple `ids` with `node_id`, `command_id` and `error_bit` from the identifier, or `(None, None)` after the timeout. `SpectralCAN.UnpackData(message, ids)` decodes the message into the object's attributes: | Message | Attributes | |---|---| | Respond_data_pack_1 | `position`, `speed`, `current` | | Respond_data_hall | `position`, `HALL_trigger`, `additional_pin2`, `hall_index` | | Send_Respond_Encoder_data | `position`, `speed` | | Send_Respond_Iq_data | `current` | | Send_Respond_Temperature | `temperature` | | Send_Respond_Voltage | `voltage` | | Send_Respond_Device_Info | `HARDWARE_VERSION`, `BATCH_DATE`, `SOFTWARE_VERSION`, `SERIAL_NUMBER` | | Send_Respond_State_of_Errors | `error`, `temperature_error`, `encoder_error`, `vbus_error`, `driver_error`, `velocity_error`, `current_error`, `estop_error`, `calibrated`, `activated`, `watchdog_error`; from 1.21 also `wrong_product` | | Send_Respond_Identity (1.21 and newer) | `product_id`, `product_name`, `tool_id`, `firmware_version`, `identity_hardware_version`, `pole_pairs`, `identity_calibrated`, `identity_flags` | | Send_Respond_Telemetry (1.21 and newer) | `temperature`, `voltage`, the error flags as above, `current` | | Respond_Parameter (1.21 and newer) | `parameters[number]` (floats for 8-16 and 20), `unknown_parameter`; `tool_id` and `watchdog_fallback` when those parameters come in | | Respond_Buffer_Data (1.21 and newer) | `capture[index]`, `histogram[bin]`, `cogging_harmonics[slot]`, `cogging_table[index]`, `encoder_table[index]` | | Send_Respond_Kt | `Kt` | | Send_Respond_Ping | `ping` (1) | | Respond_Heartbeat | `heartbeat` (1) | | Respond_Gripper_data_pack | `gripper_position`, `gripper_current`, `gripper_activated`, `gripper_action_status`, `gripper_object_detection`, `gripper_temperature_error`, `gripper_timeout_error`, `gripper_estop_error`, `gripper_calibrated` | !!! note "Object detection in the library" Library 1.20 and older assemble `gripper_object_detection` with the two bits swapped relative to the firmware, so they report 1 where the gripper sends 2 (object detected while opening) and 2 where it sends 1 (object detected while closing); 0 and 3 are unaffected. 1.21 and newer read them right.