Not start USB Device OBD after sleep mode

i get problem:

if android long start - all work ok (TV Box series4 as sample A95X AIR3)
If i use sleep mode - no connect to the USB OBD (if restart app RealDash all connect)
also OBD start work if i reconnect usb port (i can made pcb for reconnect auto)

can made trigger - re int OBD?

also i write autor firmware android and ask him about add auto restart app RealDash after sleepmode


i all ready made order in JLCPCB

and total fix this problem =)))

hardware reset usb port

Hi. I found simple decision. NC relay cut off power bus on 0.3s from X96 to USB every time by ignition on. And X96 reconnect momentarily

Relay is bad. The relay is not stable for Yusb.
The relay for the 55w lamp looks amazing, as the attenuation energy is colossal, you won’t even have time to blink an eye. But the USB port will respond instantly to microbounce.
Just don’t say that you haven’t heard anything about unreliable relay contacts while the car is moving?

I used Normal Connect relay and it is not problem. I work with auto alarm systems and we use very many relays in car. So… No, i really don’t listen about this trouble
Of course we talk about working relay, not bad

Alarms are usually active in static when the car is at rest. But your USB device is with a power rail, in the gap of which there is a relay with normally closed contacts. This device should be active when the engine is running, when the car is moving, when it starts, when the door opens and closes, when you turn the steering wheel.
I have listed the cases in which the mechanical relay contacts can open for 0.1ms. What can cause a break in the usb protocol session, and we get an unplanned restart of the USB port.
But it’s up to you! I just suggested what to avoid in such places.
I would put a mosfet with a small RC signal delay or even a controlled restart on a small MCU!

I understand you. Probably it is may be happen. And i saw it on some car. New relay usually helps.
Mosfet doesn’t work. X96 see own power bus and other power not started recognition. Need direct contacts. I will try again optocoupler. May be it will work stability.

X96 if i remeber no go to the sleep mode… current arround 400 mA ( only display off )

It is sleep very well with current 11ma. Depends of firmware. But wake up 4sec.