8 COM ports with Xmega

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Hi All

As xmega128A1 has 8 UARTS, it is possible that with a proper driver and firmware to make it an 8 USB-UART bridge that will show up on Windows as 8 separate COM ports ?

George.

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I'd have thought it'd be a lotter easier using a 128A1U ;-)

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In fact I meant 128A1U :)

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Sure, why not? You might have to extend the ASF a bit, I don't know what the upper limit is. The real problem will be throughput at high baud rates, but if they are all <100k baud it should be no problem.

I was thinking of doing something like this myself to build the ultimate battery tester. I was thinking it might be easier to use an interleaved line-by-line protocol and a single COM port though.

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angelu wrote:
In fact I meant 128A1U :)

Problem is, the USB pins are the same as one of the UARTs, so it's impossible to get all 8 UARTs running along with USB at the same time.

There's a UART REMAP bit, but all it does is move the lower UART0 to the upper nibble. I have absolutely no idea what genius thought that would have any practical value, since that just means it takes over the pins used by UART1. A *useful* remap would have been to swap Rx/Tx for XCK/, which would allow the above 8 UART + USB scenario to actually occur.