Actually the documentation is wrong. The results what you are getting are ok. The number of bytes transfered is only returned when is executed a control OUT transfer. In control IN transfers, the function returns the data read.
I'll fix that in the next release. Would mind opening a bug report at the project page? Thanks, Wander 2008/6/25 <[EMAIL PROTECTED]>: > Keep in mind that I am new to this USB and hardware hacking stuff. > > Alright I am writing this little python application to pull the firmware from > a device using the Cypress EzUSB Fx2 chip. Snazzy little thing. > > To do that you generally use fxload to load the Cypress developer > kit-supplied Vend_ax.hex code. It loads into ram, resets the cpu, and then > you can get access to some vendor commands to read and write to the eeprom. > > The reason I am doing this is because I need to have a way to verify the > firmware on any random device on of this type. This is due to some sticky > certification issues that I won't bother you with. I like python so this > seems the way to go. > > Once you get the vend stuff loaded then you use control messages to send a > request and your given a hunk of code. > > So.. it's the syntax of the controlmsg function that I have a question about. > I have everything working right now and the script is working and all that, I > just want to make sure that this behavior is 'correct'. Because once I say > this is 'finished' it'll be very difficult to change the script. > > So a truncated version of the script looks like this: > > > buses = usb.busses() > for bus in buses: > for device in bus.devices: > if device.idVendor == vend_id and device.idProduct == prod_id: > mooCow = device > > mooCowHandler = moocow.open() > > results = mooCowHandler.controlMsg(0xc0, 0xa2, data, address, 0xBEEF, 10000) > > > Ok.. so it works and it makes me very happy with good feelings and all that. > > But my question is this: > > According to the documentation I would expect that the output from the > command would be put into 'data' and the 'results' would be a return value > for number of bytes written. > > | controlMsg(...) > | controlMsg(requestType, request, buffer, value=0, index=0, > timeout=100) -> bytesWritten|buffer > | > | Performs a control request to the default control pipe on a device. > | Arguments: > | requestType: specifies the direction of data flow, the type > | of request, and the recipient. > | request: specifies the request. > | buffer: if the transfer is a write transfer, buffer is a > sequence > | with the transfer data, otherwise, buffer is the > number of > | bytes to read. > | value: specific information to pass to the device. (default: > 0) > | index: specific information to pass to the device. (default: > 0) > | timeout: operation timeout in miliseconds. (default: 100) > | Returns the number of bytes written. > > > However with my code it does something quite differently. > > The 'results' end up being a tuple of returned values! Not the number of > bytes. And the 'data' needs to be a number that tells it how many bytes I > want returned from the command! > > This is quite a bit different then what I expect after reading the docs and > thus is why I am worried. > > When I try to make the 'data' be a tuple or a list of objects or whatnot then > It'll end up being unmodified when I run the script, but the results ends up > being the number of items I put in the data list. I am confused. > > So I want to make sure that this is the correct behavior for this function. > (for it to return a tuple of the results) I am not a stickler for > 'correctitude' or anything like that, but I want to make sure that this > behavior isn't a 'bug' that is going to get 'fixed' and break my script in > the distant future. > > I am using python-usb package version 0.4.1-4 provided by Debian > Testing/Unstable. > > Thank you!! > > ------------------------------------------------------------------------- > Check out the new SourceForge.net Marketplace. > It's the best place to buy or sell services for > just about anything Open Source. > http://sourceforge.net/services/buy/index.php > _______________________________________________ > Pyusb-users mailing list > Pyusb-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/pyusb-users > ------------------------------------------------------------------------- Check out the new SourceForge.net Marketplace. It's the best place to buy or sell services for just about anything Open Source. http://sourceforge.net/services/buy/index.php _______________________________________________ Pyusb-users mailing list Pyusb-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/pyusb-users
