I might have found the problem after all. It is not the setting of the BITBANG mode that messes up the FPGA, but the reset to FIFO mode. When I just leave the second interface in BITBANG mode and simply close it after setting all necessary bits, everything works. Thanks for everyone's help on this....
Cheers, Jo On 8/12/2011 2:21 PM, Joachim Schambach wrote: > PS: > just tested the original issue for my post, namely bitbang mode. > Unfortunately, > this did not get solved by moving to Fedora 15. The bitbang mode still seems > to > toggle bits that are not in the bit mask given to the call, as the signaltap > indicates that it has an invalid jtag configuration after ftdi_set_bitmode is > called.... > Jo > > On 8/12/2011 1:49 PM, Joachim Schambach wrote: >> As another test, I installed Fedora 15 on the same machine, and then ran >> exactly >> the same program. This time, everything worked as expected, i.e. with just >> one >> call to ftdi_write_data I can call the same program several times, and every >> time I see the write in signaltap. >> BTW, I am still using libftdi 0.19 on this Fedora installation. >> >> So it seems to be a kernel problem? >> >> Cheers, >> Jo >> >> On 8/3/2011 1:39 AM, Xiaofan Chen wrote: >>> On Wed, Aug 3, 2011 at 11:17 AM, Michael Plante >>> <[email protected]> wrote: >>>> Joachim Schambach wrote: >>>>>> I am not totally sure how to interpret usbmon output, but it looks like >>>>>> all >>>>>> packets that I am requesting are actually going out. >>>> I am not either. I just know that's an intermediate troubleshooting step. >>>> There are several people on the libusb list who can help interpret it. I >>>> recommend writing there if no one gets back to you in a few days here. >>> Good suggestion. Alan Stern, for one, will help to decode the >>> usbmon log pretty fast. >>> >>> On the other hand, the usbmon does not seem to tell much if I try to >>> follow the usbmon.txt to parse the log. >>> http://www.mjmwired.net/kernel/Documentation/usb/usbmon.txt >>> >>> So maybe the problem is on the FPGA side. >>> >>> f62a4140 770501648 S Co:007:00 s 40 00 0000 0000 0000 0 >>> f62a4140 770501720 C Co:007:00 0 0 >>> http://lxr.linux.no/#linux+v3.0/drivers/usb/serial/ftdi_sio.h >>> Vendor specific request, FTDI_SIO_RESET, Reset >>> Status ok >>> >>> f62a4140 770502123 S Co:007:00 s 40 03 4138 0001 0000 0 >>> f62a4140 770502217 C Co:007:00 0 0 >>> Vendor specific request, FTDI_SIO_SET_BAUDRATE >>> Status ok >>> >>> f62a4140 770502454 S Ci:007:00 s c0 90 0000 0043 0002 2 < >>> f62a4140 770502592 C Ci:007:00 0 2 = 0000 >>> f62a4140 770502603 S Ci:007:00 s c0 90 0000 0044 0002 2 < >>> f62a4140 770502717 C Ci:007:00 0 2 = 0000 >>> Vendor specific request, FTDI_E2ROM_READ >>> (ftdi_read_chipid). >>> Status ok >>> >>> d89e87c0 841791213 S Bo:007:02 -115 100 = 00010203 04050607 08090a0b >>> 0c0d0e0f >>> 10111213 14151617 18191a1b 1c1d1e1f >>> >>> Bulk Out transfer submission, device 7, EP 2 Out, 100 bytes of data, >>> only partially (up to 32bytes, from 0x00 to 0x1f) displayed. >>> >>> d89e87c0 841792086 C Bo:007:02 0 100 > >>> Bulk Out transfer completion, device 7, EP 2 Out, 100 bytes of data, >>> status ok (means bulk out transfer is successful). >>> >>> d89e87c0 841793348 S Co:007:00 s 01 0b 0000 0000 0000 0 >>> d89e87c0 841794086 C Co:007:00 0 0 >>> >>> This is a standard set_interface request (select interface 0) >>> when the device is closed. >>> -- Dr Joachim Schambach tel: x1 512 471 1303 The University of Texas at Austin fax: x1 814 295 5111 Department of Physics email: [email protected] 1 University Station C1600 Austin, Texas 78712-0264, USA -- libftdi - see http://www.intra2net.com/en/developer/libftdi for details. To unsubscribe send a mail to [email protected]
