LIRC & FTDI: ttyUSB disappearing

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LIRC & FTDI: ttyUSB disappearing

Postby ^rooker » Tue Jan 29, 2019 1:05 am

Trying to set up an FTDI based (FT232RL) USB-to-UART adapter with a TSOP 4838 as infrared remote control receiver with LIRC.
(Xubuntu 16.04, LIRC v0.9)

The 4838 is talking to me, receiving IR signals, and LIRC's "mode2" shows reasonable output.
But after I use irrecord, the serial device /dev/ttyUSB0 just disappears :shock:

Here's dmesg output:

1) Dmesg showing that the FTDI device was successfully registered and happily waiting:
[1174334.336531] usb 2-1.7: new full-speed USB device number 35 using ehci-pci
[1174334.459497] usb 2-1.7: New USB device found, idVendor=0403, idProduct=6001
[1174334.459499] usb 2-1.7: New USB device strings: Mfr=1, Product=2, SerialNumber=3
[1174334.459501] usb 2-1.7: Product: FT232R USB UART
[1174334.459502] usb 2-1.7: Manufacturer: FTDI
[1174334.459503] usb 2-1.7: SerialNumber: A6028XXX
[1174334.461938] ftdi_sio 2-1.7:1.0: FTDI USB Serial Device converter detected
[1174334.461983] usb 2-1.7: Detected FT232RL
[1174334.462318] usb 2-1.7: FTDI USB Serial Device converter now attached to ttyUSB0

2) Dmesg saying "Goodbye" to ttyUSB0:
[1174502.814349] ftdi_sio ttyUSB0: FTDI USB Serial Device converter now disconnected from ttyUSB0
[1174502.814373] ftdi_sio 2-1.7:1.0: device disconnected


Maybe that's normal behavior when LIRC is connecting using its ftdi driver?
It's not a serial terminal (tty) anymore then.

Something else I've noticed:
The LIRC tools communicate with the FTDI device just fine (even though /dev/ttyUSBX is gone).
Yet, the RXD LED does not light up anymore when IR remote control buttons are pushed. But I see that they are received (mode2/irrecord).


To be continued...
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