The JS220 Beta program started in early October 2022 to a select group of customers and reviewers. This page serves as the starting resource for our beta customers.
The beta program hardware consisted of both the Joulescope JS220 (JS220-K000-001) and the JS220 Evaluation Kit 1 (JS220-EVK1-001). These two things will be separate, orderable products. The JS220 is our next-generation measurement instrument that improves upon the JS110. The EVK1 allows you to quickly get starting with the JS220 measuring real-world signals. You can also get starting by connecting the JS220 to your own real-world system.
- Download the Joulescope UI
- JS220 User's Guide
- JS220 Evaluation Kit 1 info
- Comparison with JS110
- GitHub repos
- joulescope_driver - New C user-space driver
- pyjoulescope - Existing python driver with joulescope_driver adapter
- jls - The latest v2 joulescope file format
- js220_end_panels - Open-source JS220 hardware end panels
- Support: Forum and firstname.lastname@example.org
We are still working on the Joulescope JS220 software support, including the new native driver. You may encounter a number of known issues while using your JS220 beta device. We are actively working to fix these issues. If you notice any issue, please email support @ joulescope.com. Thank you for your help and understanding as we work to make a great, high-quality product!
The JS220 production units fix a couple of hardware issues with the beta units:
- The beta units do not meet the USB inrush specification. We mistakenly pulled up the sensor subsystem active-low enable to the control-side 3.3V supply. Unfortunately, this 3.3V supply is delayed relative to the +5V that supplies the sensor subsystem. While this particular enable does not actually activate the sensor, it does expose a very significant amount of capacitance to the USB host for about 10 milliseconds. This capacitance is protected by a current limiter so the host should easily be able to handle the capacitance, but it does violate the USB spec. This will be fixed for the production units.
- The guaranteed minimum voltage measurement range is limited to ±13.6 V. Production units will be ±14.5 with ±14.7 typical.
Joulescope User Interface (UI)
- The following features are deprecated and no longer change behavior:
- Device rescan_interval
- The JS220 ignores the following features:
- Voltage Range (v_range)
- ext_io voltage (uses fixed internal 3.3V reference, external reference not selectable through UI yet)
- Device on_close
- The UI does not yet support streaming of gpi2, gpi3, and trigger in.
- USB Suspend is ignored. The JS220 consumes full power even when requested to suspend, which violates the USB spec's 2.5 mA max suspend current.
- Sample ids do not account for internal delays. Data from different processing paths may be unaligned.
Planned features not yet implemented
- UTC time sync
- On-instrument downsampling
- UART RX & TX support