virtual modem can't receive read IRP

NTDEV
1

Hi
I’m writting a virtual USB modem WDM driver which processes all kinds of IRPs down from modem.sys in WinXP , by transfer them in USB bus to modem device.Also this virtual modem keeps and processes UART changes.E.g. it response most of IOCTL_SERIAL_*** messages.
My question is I received only one read IRP with request length equal to 3114, after sending ATDT#777 and receiving “connect” response. I have received the LCP configuration packets from ISP many times in my buffer.But there is no read IRP, so I can’t send these LCP packets to uper driver(modem.sys). Why is there no read IRP?
If are there some errors in my UART processing?

The following are some UART states at that time.
modemstatus = 0xb0 ---->IOCTL_SERIAL_GET_MODEMSTATUS
modemcontrol=0xb0------>IOCTL_SERIAL_GET_MODEM_CONTROL

DTR is high, DCD is high.

timeout relative values:
ReadIntervalTimeout= 0xFFFFFFFF
ReadTotalTimeoutMultiplier = 0x0
ReadTotalTimeoutConstant = 0x0
WriteTotalTimeoutMultiplier = 0x4
WriteTotalTimeoutConstant = 0xFA0

chars relative values:
sSerialChars.EofChar = 0x0
sSerialChars.ErrorChar = 0x0
sSerialChars.BreakChar = 0x0
sSerialChars.EventChar = 0x7E
sSerialChars.XonChar = 0x11
sSerialChars.XoffChar = 0x13

ReadIntervalTimeout= 0xFFFFFFFF
ReadTotalTimeoutMultiplier = 0x0
ReadTotalTimeoutConstant = 0x0
WriteTotalTimeoutMultiplier = 0x4
WriteTotalTimeoutConstant = 0xFA0

wait mask = 0x432

I have received a LCP configuration packet from modem.sys and sent it to modem device by USB bus.

Can anyone help me ? I need your support.
Thank you very much!

Denny

2

Denny wrote:

sSerialChars.EventChar = 0x7E

Are you implementing IOCTL_SERIAL_WAIT_ON_MASK and IOCTL_SERIAL_SET_WAIT_MASK correctly?

DUN is waiting for 0x7E to arrive, and then it will issue another read…

3

Hi Chris:
Thank you very much!
I read my code about the IOCTL_SERIAL_WAIT_ON_MASK again. I found some errors.
I corrected them. It’s OK now.

Thank again!

Denny