HM EP1 Dual connected and communicating...but no stick inputs.

[frozen current]

Reading this page (https://www.expresslrs.org/3.0/quick-start/receivers/hmep2400/) says the receiver's led being solid means it's in bootloader mode.

My EP2 is working fine but the led stays solid. That's not in bootloader mode? This EP1 isn't seeing stick movements but the page suggests it's stuck in bootloader?

What I've tried so far:
The above link suggests some FCs don't supply enough power to their RX1. So I changed RX1 and TX1 over to RX5 and TX5, and changed the serial RX to UART5 in Betaflight. Still nothing! It's wired correctly.

Thoughts:
The RX doesn't power up with USB, like my others. I'm thinking the FC just isn't supplying enough to the RX pads? Is it worth popping a pull-up resistor in, like suggested in the above link?

[silver pier]

are you getting a C in the top right corner of the Lua Script which indicates that the receiver and Tx module is bound and Connected?

with the radio Off, does the ep dual go into wifi mode after a minute from fresh power up sequence?

[frozen current]

Yeh, C and WiFi (I flashed it yesterday via WiFi).

It seems, with a battery connected, it's fine now, since moving it to RX5 and TX5 (which is a good step forward). But still nothing on USB. Which suggests it's under-powered over USB.

So the issue has slightly changed. But I'm still thinking a pull-up 🤷 I don't want to have to lob a 6S on every time I configure. Nor do I want a live O3 sitting idle. You know.

[silver pier]

not all 5v pads can be powered by just USB

not all FCs have 5v pads that power via USB

if a pad is marked 4v5, then yes, that's usually powered by USB

[frozen current]

True. But this "latest and greatest" FC doesn't hint to what and where. Hmmm.

It might be right in front of my eyes. I'm using the 5V and GND next to the RX1 and TX1

[silver pier]

doesn't seem to be great to me if the manual doesn't indicate which pads are powered with USB or whether the silkscreened markings does

[frozen current]

Agreed

[silver pier]

mamba FCs doesn't usually have 5v pads that power via USB..

[frozen current]

Of course 🤣

[silver pier]

recent ones do power one 5v pad via usb.. the one suggested for receiver wiring, but still depends which generation of mamba FC it is..

[frozen current]

Looks like it's USB fan blowing on the O3 kind of work. Shame, as BF does the rest without battery. Just need it fully hooked up for Receiver stuff.

[silver pier]

get a multi-meter, set it to DC voltmeter mode and probe each of the 5v pad with just USB connected..
if voltmeter says it's getting at least 4.5v on the pad, then that pad powers with just USB plugged in

[frozen current]

I will do. I was going to get to that, but, like most, I wanted the quick and easy solution. Guilty of that a lot.

[frozen current]

Going through it...the only one that has anything usable on USB is the one they have earmarked for GPS. It's 4.7V. But, when powered via LiPo they all spring to life (obviously) and go to 5V. The GPS one stays at 4.7V.

Should be ok to run from that?