Greg KH wrote: > On Fri, Oct 19, 2001 at 08:51:13PM +0200, Juergen Stuber wrote: > > Hi, > > > > since there is no way to do interrupt transfers from user space > > I wrote a kernel driver for the LEGO USB Tower last weekend and > > am now trying to debug it, currently with mixed success. > > Loading/unloading, probing, and open/release seem to work ok, > > but read and write don't. > > To be more precise, it sends data left in an URB over and over > > even though I set available_length to 0, and receiving data > > doesn't work either. I guess I don't understand the way to > > handle URBs in callbacks well enough. > > Do you have a description of the USB protocol used for this device > anywhere? It would help in determining what the driver should be doing.
No, but from a captured log under W98 I figured that it basically sends/receives the data as is on the IR Port, but only once. I see urbs with exactly the data that should be sent/received according to the protocol for the Mindstorms RCX going up/down. One curious thing is that the Windows URBs may hold packets larger than the 8 byte limit. Inside the tower is a seemingly well-known chip (I don't know it though), thanks to David Wegmuller for pointing it out: > David Wegmuller wrote: > > I actually suspect that the Lego tower uses the same processor and USB > > library from ST micro-electronics (ST7263). If you don't mind, could you > > open your tower and find out? I'm just curious ;-) > > Yes, there's an SMD chip labelled ST72631M1/LPB, > ought to at least be from the same family. The previous generation of this device is connected to the serial port and sends out serial data as a 38kHz IR signal for logical 1, and nothing for 0. Serial parameters are 2400 8bit, odd parity. I used that with a terminal program for testing. Jürgen -- Jürgen Stuber <[EMAIL PROTECTED]> http://www.loria.fr/~stuber/ _______________________________________________ [EMAIL PROTECTED] To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-devel
