Originally Posted by Legodude522
|
-Bump-
Wow this is quite a project. I was just doing some research on the PXA270 to see if I can add USB host to my HTC Universal and I came across this. Good work everyone. I hope to see this project end in success.
|
Hmmm - funny you should BUMP this thread at this time - I was just thinking of doing the same yesterday after doing some more research on my earlier findings above.
It appears that the USB Client pins are multiplexed with USB Host Port 2 :exc: (from what I can descern from the various PXA270 manuals). It also appears that 6 of the USB status sensing pins are muxed with the serial port pins.
Now before you all start jumping for joy, I need to determine what's between those pins on the actual CPU chip and the edge connector of the Axim. If it's simple buffering, then a re-write of a few drivers as well as a simple interface cable is all that might be needed in order to give the X50/X51 series that elusive USB Host interface.
Of course, the big item here is the re-write of the drivers. Essentially, the USB OTG Host interface is actually controlled by the USB
Client port control registers. That is why I missed it a while back - I was concentrating on the USB Host interface registers and hardware for USB Host Port 1. No
internal hardware mods would be needed by using USB Host Port 2.
The original client driver would need to be rewritten to allow sensing of the USB Vbus voltage through one of the serial pins, which means the serial interface driver needs to be rewritten as well. I will be looking at the drivers from the Asus 730W PDA as it uses a PXA270 and has a USB Host interface. I need to find out how its host interface has been implemented. I was also looking at the new HTC Advantage which is, in effect, what everyone here wanted in a 'new' Axim. Only the price is waaaay too high (at this time) - but it has a USB host interface and it was designed by HTC who designed the Axim, so who knows......
Enough talk - I need to get back to playing with my toys
