Two Joulescopes intermittently fail to connect to my Windows 10 PC. The green light remains unilluminated after connection and I repeatedly hear repeated tones (indicating a new USB connection). The logs show the retry pattern, too. The cycle below repeats indefinitely when the connection fails.
WARNING:2021-03-25 09:04:49,814:driver.py:984:joulescope.driver:status failed 1: usb control transfer failed: [1] Incorrect function.
WARNING:2021-03-25 09:04:50,318:driver.py:984:joulescope.driver:status failed 1: usb control transfer failed: [1] Incorrect function.
WARNING:2021-03-25 09:04:50,813:driver.py:984:joulescope.driver:status failed 1: usb control transfer failed: [1] Incorrect function.
INFO:2021-03-25 09:04:51,312:main.py:951:joulescope_ui.main:_on_recoveryTimer
WARNING:2021-03-25 09:04:51,313:driver.py:984:joulescope.driver:status failed 1: usb control transfer failed: [1] Incorrect function.
INFO:2021-03-25 09:04:51,313:main.py:943:joulescope_ui.main:_device_recover: start
INFO:2021-03-25 09:04:51,313:main.py:1027:joulescope_ui.main:_device_scan start
INFO:2021-03-25 09:04:51,314:main.py:1041:joulescope_ui.main:current device = Joulescope:002180, False
INFO:2021-03-25 09:04:51,314:main.py:1047:joulescope_ui.main:_device_scan done
Today, I was finally able to restore communication by connecting directly to my PC. My USB hubs are all externally powered, so should be capable of supplying necessary power.
Previously, rebooting my PC didn’t remedy the problem.