I have a couple of assembled Gen3a units here that have yet to find homes.
Thank you Mark, for the PCB HomeBrew 3a
Everything works right away. A Beitian 180 GPS module is installed, the warm start under the open sky takes 5 seconds, the cold start about a minute.
I built an internal solution. There is no AUX socket soldered on, but 6 lines that are looped through to the hand controller connection using a self-made adapter. If someone interested I can present this internal solution. There is also a HomeBrew USB port under the battery cover for easy updates without disassembling the Mount.
During the tests I noticed something that is a bit strange: The GPS can be switched on and off in the utilities, which also works.
Menu/Utilities/GPS on/off. Then press "Enter". The message "Press Enter to Turn GPS off" appears. If you are listening on the AUX bus, the command to turn off the GPS is already being sent, even though the "Enter" key to confirm the command has not been pressed. This can be checked by selecting Menue/View Time-Site. "Saved Site" is then displayed here, not "GPS Linked". Accordingly, the GPS was actually switched off. The behavior is the same the other way around, i.e. if you switch Menue/Utilities/GPS on/off. Then press "Enter". The message "Press Enter to Turn GPS on" appears, the command is then executed, although the required confirmation with "Enter" is missing.
In my opinion, this behavior is an error in the firmware of the NexStar SE and has nothing to do with whether the GPS is connected via a HomeBrew or with the original module from Celestron.
This behavior can be very confusing, because if you rely on the commands of the NexStar SE with the hand controller, then you are looking for a bug in the HomeBrew that the HomeBrew does not have.
I am interested to know whether other owners of a NexStar SE also confirm this behavior or whether the error in the firmware cannot be observed there.
Concrete:
I see the message "GPS on/off" on the display of the hand controller, I confirm with Enter and see "Press Enter to Turn GPS on" and the following is then output in the serial monitor:
14:21:15.423 -> 016971826 auxbus_rx: 3b 03 0d b0 fe 42
14:21:15.509 -> GPS GET_VER
14:21:15.509 -> 016971910 auxbus_tx: 3b 05 b0 0d fe 02 00 3e
[you can find out where I live that way, but I don't care :-) ]
When the command is requested to be confirmed with the Enter key, nothing is displayed in the serial monitor, so this "Enter" command has no consequences and has already been executed before.
The NexStar has been provided with the latest updates.
What about your NexStar SE?
Edited by SieglindeFestkochend, 04 February 2023 - 08:22 AM.