I have been able to compile the OnStepX and flash the ESP32, but I had to use PlatformIO. The Arduino IDE was just exiting the build before even starting to compile with no error message, even after turning on verbose error messages. I prefer PIO in command line mode anyways.
My plan is to use a Raspberry Pi along with OnStep to host a camera and to try out things like Astroberry, etc. I'm trying to figure out how best to connect it to the OnStep controller. I know that wifi (and maybe bluetooth) would work, but it's going to be in the same box, so I thought a hardwired connection would be best. I also have been able to build the firmware on the pi using PIO, and it would be handy, at least initially, to be able to reflash the EXP32 from the pi.
I tried connecting to J13 (the 1x5 header), thinking that might be the same UART as is used to program it from USB, but, I'm just getting a stream of garbage characters from that, like it is at the wrong baudrate. I could connect via USB, but I'm concerned about the power connection. In that case, it seems like I would need to modify a USB cable to not provide power.
Has anyone made such a connection to a pi with an ESP32 board, or know why it would not be working? It appears I believe the pins on that connector are the right ones (TX/RX0), and I don't see them going anywhere, so I don't understand why there would be.
I'm also noticing that the voltage regulator on the ESP32 board gets unusually hot when in the board, and the board pulls close to 0.5A at 12V (running off of a bench supply), This is with nothing plugged into the board other than the ESP32 (no D1, stepper drivers, or USB). The LED is pretty much solid RED, which I think means that it's sending data constantly. If I pull the board out and connect via USB it seems okay. I'm currently trying to just connect the board via jumper wires (just +5 and GND connected ATM) to see if I can track down the problem.
6W is way more than the maximum draw should be, and it seems to be something in the firmware that's causing it, since it works normally for a while, so I'm confused on what is going on. The VREG must be for 3.3V, so I suspect the issue will show up when I connect that to the board.