Hi Greg, I have a UART device driver which is used to control some MCM ( Monitor & control module ) devices with address like 2,3,5,10,14 & 0 thru serial port using RS-485 interface card. Now I want to control these devices thru usb-serial adaptor card.When I plug the usb-to-serial device.It's shows me the terminal ttyUSB0. I tried sending data thru it , but in between some junk data is also going out .... output of usbmon : ee26be80 3612838323 S Co:7:002:0 s 40 01 0008 0000 0000 0 ee26be80 3612839660 C Co:7:002:0 0 0 ee26be80 3612839716 S Co:7:002:0 s 40 01 0009 0000 0000 0 ee26be80 3612840660 C Co:7:002:0 0 0 ee26be80 3612840700 S Ci:7:002:0 s a1 21 0000 0000 0007 7 < ee26be80 3612841661 C Ci:7:002:0 0 7 = 80250000 000008 ee26be80 3612841710 S Co:7:002:0 s 21 20 0000 0000 0007 7 = 80250000 000008 ee26be80 3612842659 C Co:7:002:0 0 7 > ee26be80 3612842672 S Co:7:002:0 s 21 22 0003 0000 0000 0 ee26be80 3612843657 C Co:7:002:0 0 0 ee2b3800 3612843712 S Ci:7:002:0 s a1 21 0000 0000 0007 7 < ee2b3800 3612844658 C Ci:7:002:0 0 7 = 80250000 000008 ee2b3800 3612844668 S Co:7:002:0 s 40 01 0000 0000 0000 0 ee2b3800 3612845660 C Co:7:002:0 0 0 ee0eaf80 3612845669 S Bi:7:002:3 -115 256 < ee0ead00 3612845674 S Ii:7:002:1 -115:1 10 < ee2b3800 3612845679 S Co:7:002:0 s 21 22 0003 0000 0000 0 ee2b3800 3612846657 C Co:7:002:0 0 0 ee0ea680 3618022849 S Bo:7:002:2 -115 100 = 00080000 00000000 f8000000 00000000 00000000 00000000 00000000 00000000 ee0ea680 3618024532 C Bo:7:002:2 0 100 > Ideally data which should go out is : 0080000000f8.( device address is 0 and check sum is f8 ). In my previous emails, you told me to use current kernel version..so I am now using 2.6.35 kernel version. kindly help me. Thanks- Raj. -- Open WebMail Project (http://openwebmail.org) -- 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