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.