On Fri, 4/24/09, Tony N. [email protected] wrote:
The short answer is that the PIC 18F4550 processor will not help.
USB needs a “host” (typically a PC) that times & controls each data
packet and a “device” to talk to. Optionally a hub is both a device
and relay of timing & data to further devices. Both the PIC processor
and the USRP are devices, and cannot talk to each other.
So USB device can only talk to USB Hub.Thanks for this clarification.
Also the USRP documentation says it needs “USB2”, which I
think means it needs the “High Speed” data transfer of USB2. Whereas
the PIC 18F4550 only supports the lower transfer speeds of USB1.1
I mentioned PIC16F4550 as an example for mcu that has a USB port.
Actually, I didn’t checked whether it supports HS or FS (Sorry for bad
An easier path would be to look small processor boards such as those
that support embedded Linux. For instance the web page for the
Gumstix Overo Earth says it has a “USB HS Host” and a micro SD slot.
(Not micro SDHC - so you are limited to, I think, 4Gb cards.)
Thank you for your suggestion, but I’m looking for cheep and simple
method to load USRP firmware.