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Cant run Test635 :(


New member

I am newbee on linux and I have a lot of exprience with C and C++.

I want to run 635 with a SBC (it has a revised version of BusyBox Linux). But firstly I tried it with SUSE 10.

I compiled the test program and tried to run it.

./test635 /dev/ttyUSB0 115200

Ultra-simple CFA-635 command-line communications example.
Crystalfontz America, Inc. http://www.crystalfontz.com

./test635 PORT BAUD
PORT is something like "/dev/ttyS0" or "/dev/usb/ttyUSB0"
BAUD is 19200 or 115200
To clear the display, enter "clear" as an optional third parameter

Serial_Init:: Open() failed
Could not open port "/dev/ttyUSB0" at "115200" baud.

It couldnt open the port. I trýed with ttyUSB1 but it didnt work again.

From the forum I found some tips.

I looked at /proc/bus/usb/devices

T: Bus=03 Lev=01 Prnt=01 Port=00 Cnt=01 Dev#= 2 Spd=12 MxCh= 0
D: Ver= 2.00 Cls=00(>ifc ) Sub=00 Prot=00 MxPS= 8 #Cfgs= 1
P: Vendor=0403 ProdID=fc0d Rev= 2.00
S: Manufacturer=Crystalfontz
S: Product=Crystalfontz CFA-635 USB LCD
S: SerialNumber=CF00000001
C:* #Ifs= 1 Cfg#= 1 Atr=80 MxPwr=490mA
I: If#= 0 Alt= 0 #EPs= 2 Cls=ff(vend.) Sub=ff Prot=ff Driver=ftdi_sio
E: Ad=81(I) Atr=02(Bulk) MxPS= 64 Ivl=0ms
E: Ad=02(O) Atr=02(Bulk) MxPS= 64 Ivl=0ms

And I saw the driver is ok

I wonder how we decide which tty device we will use

and what I can do more.

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USB LCD Displays - Graphic and Character LCDs with a Keypad

CF Mark

I gather that /dev/ttyUSB0 does exist, or was that just a guess from the example?

Look in your boot up logs (if you keep them), when the FTDI driver is loaded it should say what device name its using.