googling a bit more about the problem, I've found that this is a common misbehaviour of some faulty hardware. In an "ancient" mail dated 2005 greg asked for the output of /proc/bus/usb/devices/ , so here is mine: T: Bus=02 Lev=02 Prnt=02 Port=01 Cnt=01 Dev#= 10 Spd=12 MxCh= 0 D: Ver= 1.10 Cls=00(>ifc ) Sub=00 Prot=00 MxPS=64 #Cfgs= 1 P: Vendor=067b ProdID=2303 Rev= 3.00 S: Manufacturer=Prolific Technology Inc. S: Product=USB-Serial Controller C:* #Ifs= 1 Cfg#= 1 Atr=80 MxPwr=100mA I:* If#= 0 Alt= 0 #EPs= 3 Cls=ff(vend.) Sub=00 Prot=00 Driver=pl2303 E: Ad=81(I) Atr=03(Int.) MxPS= 10 Ivl=1ms E: Ad=02(O) Atr=02(Bulk) MxPS= 64 Ivl=0ms E: Ad=83(I) Atr=02(Bulk) MxPS= 64 Ivl=0ms 2012/2/8 pierigno <pierigno@xxxxxxxxx>: > hello, > > following mr Greg's bot advice, I'm sending this email tore you, > hoping to get more insight on this matter. > > > I'm having some problems trying to communicate with a home router > device using a PL2303 based usb-to-serial converter. > > My linux-based router exposes a UART interface (with TTL levels, > 155200 baud rate, 8N1, no hardware flow control) trough which is > possible to visualize its initialization output and possibly interact > with the built-in boot manager (yamon). So far,sadly, I was only able > to receive the output sent by the device, but nothing more: any attept > to send commands failed. Actually I'm able to see what I transmit only > if I short-circuit TX and RX (leaving GND connected), so the wiring > should be correct (Actually while gathering logs, I've found that if I > detach the adapter, then reattach it again, I can actually send a > break signal (through Control+A F sequence in minicom). After that > however, I cannot send data anymore). > > I've tried many different programs, minicom, putty,gtkterm, screen, > but the behaviour seems the same. > > I've gathered some logs with usbserial and pl2303 modules loaded with > debug=1 and have attached them to this email: > > - pl2303-usb.txt is output of lsusb -vvv > - usbserial-pl2303.log is the output of 'cat /var/log/messages' > - minicom-strace is the output of 'strace -o minicom-strace minicom' > - minicom-capture.log is the text coming from the router as captured > by minicom > > Hope it helps.If there are other better ways to debug this > behaviour or you need other info, please, tell me, I will manage to > provide the needed nformation. > > Best regards, > > Pierangelo Terzulli -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
