The built-in Wifi of my new EVO-8 seems to be poorly implemented (big surprise, not!) -- if the connection with my smartphone ever lapses, the mount requires a power-cycle before it ever works again. That's just poor programming in the mount electronics, a lack of basic fault tolerance considerations. The fault is definitely on the mount side, not the app. The mount simply doesn't appear to accept a "new" connection when it thinks the "old" connection is still there, even though it isn't alive at the other end.
So.. solution is to roll one's own more reliable wireless option(s), as a small box that plugs into an AUX port on the mount. This thread will help document and share the efforts, and anyone is welcome to join in and play along.
An ESP32 dev board, with both bluetooth and Wifi built-in, is a good starting point. These cost between CAD$12 and CAD$25 on Amazon, or less than that direct from Asia. I'll be using one of those, probably a "NodeMCU-32S" style variant. These are 3.3V boards, and are NOT designed to tolerate 5V logic inputs from the mount. So a discrete 74LV136 chip will likely be wired in to buffer/tristate the bus lines and also to do the 5V <--> 3.3V level conversions.
Some effort may be needed to figure out the protocols -- as near as I can tell, no-one else has documented interfacing Wifi or Bluetooth directly to the AUX bus -- most tend to use the serial port on one of the older generation hand controllers instead.
My first effort today was to plug the logic analyzer into the EVO mount, and observe what happens when a wifi connection is used with the built-in wifi stuff. I am very happy to have discovered that nothing "fancy" at all is involved. The Wifi appears to show up as DEV_ID=0x20 on the bus, and otherwise speaks the same protocols as the hand-controller and other devices do. Good!
So next up will be to have a quick peek at the IP packets (most likely TCP on top of IP) going back and forth and see if they use the same raw AUX bus protocol, or if a bit of translation is needed from one side to the other.
The ESP32 board I first acquired for this job is faulty -- repeated boot loop whenever bluetooth is enabled -- so it's going back to Amazon and a replacement is on the way for this coming week.
I expect to first try and get Wifi going, because that's all that SkyPortal seems to grok. But I'd very much prefer to use bluetooth, so that the smartphone 1) can stay internet connected where feasible, and 2) will stop complaining that the Telescope doesn't provide internet connectivity! Skyportal doesn't do bluetooth, but SkySafari apparently does. There's also an Android app out there which can be used to redirect bluetooth to make it appear to be coming from an IP address (eg. wifi) instead -- if that works, then this would enable a bluetooth connection to work with SkyPortal! Yay!
For easy reference, here's a link to the (paid, but cheap) BT/USB/TCP Bridge Pro app for bridging connections on Android:
More when I have more. Feel free to join in.
Edited by mlord, 06 December 2020 - 04:34 PM.