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+# kappanhang
+
+kappanhang remotely opens audio channels and a serial port to an Icom RS-BA1
+server. The app is mainly developed for connecting to the Icom IC-705
+transceiver, which has built-in Wi-Fi and RS-BA1 server. All features of the
+protocol are implemented including packet retransmission on packet loss.
+
+kappanhang currently only supports Linux, but support for other platforms can
+be easily added if anyone is interested (volunteers needed).
+
+## Compiling
+
+You'll need Go installed on your computer.
+
+```
+go get https://github.com/nonoo/kappanhang
+go install https://github.com/nonoo/kappanhang
+```
+
+## Required settings on the RS-BA1 server (the transceiver)
+
+- Set the username to **beer** and the password to **beerbeer**.
+  These are fixed as the password encoding of the RS-BA1 protocol has not been
+  decrypted yet. See [passcode.txt](passcode.txt) for more information.
+- Leave the **UDP ports** on their default values:
+  - Control port: 50001
+  - Serial port: 50002
+  - Audio port: 50003
+- Leave the **Internet access line** on the default **FTTH** value.
+
+## Running
+
+You can get the available command line parameters with the **-h** command line
+argument.
+
+If no command line arguments are set, then the app will try to connect to the
+host **ic-705** (ic-705.local or ic-705.localdomain).
+
+After it is connected and logged in:
+
+- TODO: audio
+- It starts a **TCP server** on port 4533 for exposing the **serial port**.
+  This can be used for controlling the server (the transceiver) with
+  [Hamlib](https://hamlib.github.io/):
+
+  ```
+  rigctld -m 3085 -r 127.0.0.1:4533
+  ```
+
+  3085 is the model number for the Icom IC-705. `rigctld` will connect to
+  kappanhang's TCP serial port server, and waits connections on it's default
+  TCP port 4532.
+
+  To use this with for example [WSJT-X](https://physics.princeton.edu/pulsar/K1JT/wsjtx.html),
+  open WSJT-X settings, go to the *Radio* tab, set the *rig type* to **Hamlib NET
+  rigctl**, and the *Network server* to `127.0.0.1:4532`.
+
+If the `-s` command line argument is specified, then kappanhang will create a
+virtual serial port, so other apps which don't support Hamlib can access the
+transceiver directly. Look at the app log to find out the name of the virtual
+serial port.
+
+## Donations
+
+If you find this app useful then [buy me a beer](https://paypal.me/ha2non). :)