Originally Posted by kriketronic
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thanks afarre.
I'm going to read it at night.
If someone has the hardware hacks and wm5 installed can test the cab from eten 600?
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Unfortunately, it's not that simple. The PXA270 CPU chip (it's actually an SoC - System on a Chip) has several USB interfaces. It has 1 client and 3 host interfaces and there is no guarantee these are at the same I/O addresses as the ETEN devices.
After about 6 months of not touching this project, I decided to take another quickie look at the PXA270 docs and programmers reference. What I now see is very interesting.
Originally, I was looking at bringing out the USB Host 1 interface pins to the outside world as they were only terminated internally on the motherboard. Only about 1% of users might be able to do that.
I then started to look at the USB OTG (On The Go) interface that this chip supports. The USB OTG interface can be used as both a client and host. It shares the same pins as the Axim's serial port. Unfortuately, there are two serial control lines pins that are not brought out to the connector, so I scrubbed that idea.
This past weekend I picked up the programmer's design reference book to look at how the various USB interfaces are programmed and I saw something that I missed before as this was in the USB Client section. It appears (to me anyways) that the USB Client pins can also be programmed to act as a USB Host when in the USB OTG low power operation mode. The manual discusses how the additional control registers are used along with an output mux and charge-pump circuit (to provide the +5v). Refer to the PXA27x Processor Family Developer's Manual - dated Jan 2006, sections 12.5.2 and 20.
I will be looking at this more closely to see if a simple driver can be written (Afarre, where are you...
) to switch the USB client pins into Host mode. In addition to this, the USB device drivers would be needed. Please remember, an additional IO interface circuit will be needed to connect between any USB device and the Axim as the proper voltages are not on the sync connector.