I have an HL7812 connected to USB.
It represents itself as four devices, ttyACM[0-3].
I’ve not found in the documentation what each of these is used for. What data is expected on each port?
Thanks,
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Thank you!
I’ve seen descriptions of the ttyACM[0-2] devices, but I have a fourth port that is not mentioned anywhere.
My guess is that ttyACM[0-1] is for AT/Data and ttyACM2 for GPS, but I have not got it confirmed.
Still no clue what ttyACM3 is for.
What is the return of AT command kusbcomp
Hi,
AT+KUSBCOMP?
+KUSBCOMP: 1,1,2,3
OK
AT+KUSBCOMP=?
+KUSBCOMP: (0-1),(0-5),(0-5),(0-5)
OK
So I intepret it as
ttyACM0 = AT
ttyACM1 = AT_PPP
ttyACM2 = NMEA
Even the AT commands interface guide does not mention the 4:th port.
Is the ttyACM0 perhaps an USB/UART port that persist even if I disable USB?
what is your testing result on disabling USB?
Actually i think you can just ignore that port, most likely you only need AT port
All ttyACM devices disappear, kind of expected 
Anyway, It seems to be ttyACM[0-2] that I should use, I will leave ttyACM3 as an unresolved mystery.
Thank you