# greenctld
Controller software for Green Heron RT-21 Az/El.

![Green Heron RT-21 Az/EL Alfa SPID](img/greenheron-alfaspid.png)
*Green Heron RT-21 controller with Alfa SPID RAS*


# Install
Install thusly:

```
sudo apt install python3-virtualenv python3-pip
git clone https://spacecruft.org/spacecruft/greenctld
cd greenctld
virtualenv -p python3 env
source env/bin/activate
pip install --upgrade pip
pip install -r requirements.txt
```


# SatNOGS-client
HOWTO connect to the Libre Space Foundation's
SatNOGS network? Not sure.


The Green Heron RT-21 driver that has been in Hamlib for a decade
only supports one USB port. Th Green Heron RT-21 Az/El has one
USB port for azimuth and one USB port for elevation. This makes
the Hamlib driver that has been in Hamlib for 10+ years unsuitable
for use with an Az/El antenna setup. In sum, the hardware isn't
plug & play with `satnogs-client`.


There is a driver under a libre license available upstream here:

* https://github.com/mct/greenctld

The `greenctld` in that repo was written for Python 2.
The present `spacecruft` repo ports it to Python 3.
This is mostly done.
The `greenctld` daemon listens on port 4533 similar
to `rotctld`. It is unclear to me how to get the
`satnogs-client` to use this port instead of wanting
to start it's own `rotctld`.


In July of 2021, a commit was made to the main Hamlib
repo that added dual USB control for the Green Heron
RT-21 Az/El. This commit is not in the Hamlib version
that is in the latest `satnogs-client` release, however.
The new version adds a second controller command line
option:

```
  -r, --rot-file=DEVICE         set device of the rotator to operate on
  -R, --rot-file2=DEVICE        set device of the 2nd rotator controller to operate on
```

One option would be to adapt `satnogs-client` to use this new version.
Another option would be to port these patches back to the version
`satnogs-client` is running.


## SatNOGS Connection Options
Which option to use to connect the Green Heron RT-21 to `satnogs-client`?
Possibilities:

* Configure `satnogs-client` to use `greenctld` instead of `rotctld`.
* Patch `satnogs-client` to use recent Hamlib (no changes to Hamlib).
* Patch Hamlib with backported dual USB patches (no changes to `satnogs-client`).
* Other.


# Upstream
Upstream Python 2 version.

* https://github.com/mct/greenctld

Copyright (c) 2017, Astro Digital, Inc.


# License / Copyright
Port from Python 2 to Python 3 of mct's greenctld.
Same as upstream, permissive license, see `LICENSE`.

Documentation License: CC By SA 4.0 International.

Source:

* https://spacecruft.org/spacecruft/greenctld


Copyright (C) 2022 Jeff Moe.