Like many people here, I wanted to make an arduino physical display then quickly realized unity does not have the required serial IO name space. So the solution is to borrow someone else's code (http://sourceforge.net/projects/serialportnet/), which turns out is kind of incomplete but works. This plugin sends/receives data packets over the serial port, which should make it much easier for people wanting to build hardware for KSP but can't be bothered with making plugins as well.
Note: currently not fully working for windows 10 for some reason! You can receive data from KSP but not control anything.
Compatible with KSP 1.2. Versions 0.18.2 and older compatible with 1.1, 0.17.6 and older compatible with 1.0.5, 1.0, 0.90, versions 0.15 and older compatible with 0.23, 0.23.5, 0.24, 0.25
This plugin implements the following:
Packeting of serialized C# structure for efficient communications including checksums
Listing of available serial ports (only works on Windows PC, using registry hacks)
Automatic handshake and detection of display COM port at 38400 Baud
Bi-directional data transfer: control KSP from arduino [supported but not fully implemented yet, easy if you want to do it yourself] (added in 0.13)
Analogue axes control (added in 0.14)
Check forum link for details: http://forum.kerbalspaceprogram.com/index.php?/topic/60281
Released on 2019-08-27
Added pro-grade, maneuver, and target pitch and heading angles, as well as normal vector, thanks to @c4ooo Recompiled against KSP version 1.6.1, seems to work OK in 1.7.3 Use Arduino demo 17
Released on 2017-06-10
Fixed broken axis/SAS control issues reported by @Freshmeat and @#Pseudo
Rebuilt against KSP 1.3 (previous version seem to work still, so this is just in case something changed)
Released on 2017-04-23
17-10-2016 V0.18.4 Changed MNDeltaV from node delta V required to deltaV remaining (thanks @JeffSergeant), Added float TargetDist: Distance to targeted vessel (m), Added float TargetV: Target vessel relative velocity (m/s)
22-10-2016 V0.18.4a Fixed a null reference bug when targeting a planet
19-11-2016 V0.18.5 Added SAS mode input and output (thanks @c4ooo), see page 68 for details
03-12-2016 V0.18.6 Added navball mode input and output (again thanks to @c4ooo, hero of the republic), Added easy to use functions to set and read SAS and navball modes, see page 70 for details
23-04-2017 V0.18.7 Fixed broken axis control hooks reported by @AmeliaEatyaheart and @Freshmeat
Released on 2016-10-13
Compatibility with KSP 1.2
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