Bluetooth Low Energy Data logging for J7-C/UC96 USB Digital Power Testers
Requires gattlib.
Sadly there has been an API change with newer bluetooth adapters (HCI5) which isn't supported by gattlib yet. If you see a Set scan parameters failed error, your adapter may be using >=HCI5 and not be supported until the code has been ported to dbus/bluez or gattlib is updated.
Just start the script to show the measurements of the first found J7-C on screen.
usage: j7c-gat.py [-h] [-v | -q] [-d DEVICE] [-w] [-r] [-H HCI]
[-T SCANTIME] [-m {Text,CSV,JSON,RAW,InfluxDB}]
[-O OUTPUT] [-a] [--csv-delimiter CSV_DELIMITER]
[--csv-no-header] [--json-pretty] [--raw-header]
[--raw-pretty]
Receive measurement values from a J7-C USB power monitor using BLE
options:
-h, --help show this help message and exit
-v, --verbose increase output verbosity. Repeat for higher
verbosity (max. 5)
-q, --quiet suppress non-data output messages
Device control:
-d DEVICE, --device DEVICE
target device MAC address. If no address is given
the first compatible device found will be used
-w, --wait wait for device to appear
-r, --reconnect wait and reconnect when loosing connection
-H HCI, --hci HCI HCI used for communication. Defaults to hci0
-T SCANTIME, --scantime SCANTIME
Time in seconds to scan for devices. Defaults to 2
Seconds
Output options:
-m {Text,CSV,JSON,RAW,InfluxDB}, --mode {Text,CSV,JSON,RAW,InfluxDB}
output type
-O OUTPUT, --output OUTPUT
output file, device or network address
([tcp|udp]://[host_or_ip]:port)
-a, --append append output if it is a file
Output options for CSV:
--csv-delimiter CSV_DELIMITER
CSV delimiter. Default: ';'
--csv-no-header Omit CSV header
Output options for JSON:
--json-pretty Use pretty-print for JSON Output
Output options for RAW:
--raw-header Add address header
--raw-pretty Use pretty-print for RAW Output
The decoder was reverse engineered by myself. There are now a few more comprehensive protocol descriptions available, so if you want to work with these devices yourself you might want to have a look over there: