Transition to v1

The launch of the JS220 in 2022 introduced a new API based upon publish-subscribe. You can find the source code at joulescope_driver. We encourage all new code to use this API directly.

However, this project provides a backwards-compatible v0 convenience wrapper. Access the wrapper through any of the scan functions:

  • scan

  • scan_require_one

  • scan_for_changes

These scan functions return Driver wrapper instances compatible with the v0 API. The Driver wrapper removes the following methods found in the v0 API:

  • Driver.usb_device

  • Driver.bootloader

  • Driver.run_from_bootloader

  • Driver.calibration_program

  • Driver.enter_test_mode

The Driver.serial_number now returns Driver.device_serial_number.

Parameter support has also changed. The following parameters have modified behavior:

Parameter

JS220

JS110

sensor_power

ignored

ignored

source

ignored

ignored

i_range

v_range

15V,5V→15V,2V

ovr_to_lsb

io_voltage

ignored; use Vref

gpo0

gpo1

current_lsb

enables gpi0

voltage_lsb

enables gpi1

current_ranging_type

ignored

current_ranging_samples_pre

ignored

current_ranging_samples_window

ignored

current_ranging_samples_post

ignored

buffer_duration

reduction_frequency

sampling_frequency

New JS220 topics are available as parameters. However, the parameter metadata is retrieved dynamically and is not available until the device is opened.