On Thu, 13 Jan 2005, Mohan V wrote: > Hello All, > > I am using usbser.sys(Windows Host) and generating Virtual COM port. > My device side application writes 2000 bytes to that port. The host side > application reads some data, comes out of read and parses the first 2 > bytes to get the actual length of data to read, and then issues a read > call with that much amount of data to read. But the application is able > to read only 56/59 bytes of data and getting transmission timeout from > the device side driver. The transmission timeout is 5secs in the write > routine of device side driver. > > Is it because the host side appln. is coming out of read and issuing one > more read? Doesn't the host buffer the data?
You'll find that a lot of people on the _Linux_ USB development list don't know very much about how _Windows_ hosts behave. > Also i wanted to know if a full speed device wants to transfer data > whose size is greater than max packet size of bulk endpoint(64 bytes in > this case), does the device has to wait for IN packet from the host > after every 64 bytes of transfer? Yes it does. However a gadget driver can queue more than 64 bytes in a single request. The device controller will send out the data in 64-byte packets, each in response to a single IN packet from the host. Alan Stern ------------------------------------------------------- The SF.Net email is sponsored by: Beat the post-holiday blues Get a FREE limited edition SourceForge.net t-shirt from ThinkGeek. It's fun and FREE -- well, almost....http://www.thinkgeek.com/sfshirt _______________________________________________ [email protected] To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-devel
