Thanks to help on this forum I was able to resolve this issue and get FTDI up and running. starting from examples/bitbang.c, I made a simple bulk transfer throughput test to measure the effect of baudrate and block size
the results executing on x86 show a dramatic difference. starting with default block size of 64 bytes/9600 "baud" yieds around 250Kbit/second, to 4096 block size/921600 baud yields over 4.5Mbit/sec but now I'm starting to wonder about whats going on "under the hood" so to speak. for starters, what is the effect of ftdi_set_baudrate()? is this like a classic serial port rate, or can an arbitrary clock rate be selected? it seems to limit out at some point and return an error. its hard to tell for sure whats going on in the chip since there is no register level spec. bitbang.c includes a couple of steps that seem optional: "turning everything on", and "turning everything off", writing 0x0 and 0xff respectively to the bulk endpoint. Is that just required for bitbang? because the thruput test works OK without it. and what the heck is ftdi_enable_bitbang() doing? writing to the control endpoint? Anyway will be happy to share the results of our testing as this progresses... /Steve -----Original Message----- From: Laurent Perez [mailto:[email protected]] Sent: Wednesday, February 11, 2009 11:41 PM To: [email protected] Subject: Re: libftdi missing definition for usb_dev_handle Hello Steve, > now I am trying try track down usb.h (Erdfelt) containing a reference > to usb_dev_handle. It does not appear in libusb-1.0.0, nor in > libftdi. so it must be a system file? libusb-1.0 is not backward compatible with the good old libusb-0.1. In order to build and run programs that rely on libusb-0.1, you will need to instal libusb-compat-0.1 compatibility layer [1]. You probably only miss header file from this package. The lib itself should already be installed on your system as much of usb relative tools hasn't been ported to new libusb-1.0. Regards ; Laurent. Links : ¯¯¯¯¯¯¯¯¯¯¯¯ [1] http://libusb.wiki.sourceforge.net/LibusbCompat0.1 -- libftdi - see http://www.intra2net.com/en/developer/libftdi for details. To unsubscribe send a mail to [email protected] -- libftdi - see http://www.intra2net.com/en/developer/libftdi for details. To unsubscribe send a mail to [email protected]
