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README.md

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+# powenetics-v2
+
+Library and CLI application for power and energy measurements using the [Powenetics v2](https://hwbusters.com/psus/powenetics-v2-power-measurements-device-review/) device. Written in Rust. Tested only on Linux. Should work on Windows, too (I guess).
+
+## Usage
+
+### TL;DR
+```
+$ cargo build
+$ target/debug/powenetics-v2 --csv power.csv /dev/ttyACM0
+```
+
+### Detailed Usage
+Connect the Powenetics v2 device via USB. 
+Powenetics v2 communicates via Serial-over-USB, so you will have to figure out the right serial port. 
+Running `powenetics-v2` without any arguments will print a list of available serial ports where the right one is typically (probably not on Windows) marked as "USB".
+Depending on your Linux distribution, it might be necessary to configure the appropriate file permissions for accessing the port.
+Physical replugging is required in case any error occurs as there is no other way to reset the device. 
+
+```
+$ powenetics-v2 --help
+Powenetics v2 command line tool
+
+Usage: powenetics-v2 [OPTIONS] [PORT]
+
+Arguments:
+  [PORT]  Serial port name or path (run without arguments for list of available ports)
+
+Options:
+      --csv <path>  Write measurement data to CSV file
+  -h, --help        Print help
+```
+
+## Output
+
+Currently only CSV file output is supported. 
+Output consists of voltage (mV), current (mA), and accumulated energy (nJ) for each channel. 
+Powenetics v2 provides ~1000 updates per second.
+Measurement data is provided for the following channels (in this order):
+
+* ATX 3.3V
+* ATX 5V Standby
+* ATX 12V
+* ATX 5V
+* EPS 12V #1
+* ATX12VO 12V Standby
+* EPS 12V #3
+* EPS 12V #2
+* PCIe 12V #3
+* PCIe 12V #2
+* PCIe Slot 3.3V
+* PCIe Slot 12V
+* PCIe 12V #1