Why does there appear to be redundant pins used for two signals on the PXA270-10 Card Engine?

This was done on purpose to meet our standard Card Engine pinout. IRDA signals typically come off on B30, B31. UARTC signals typically come off of B46, B47. For the PXA270 processor, the signals GPIO46, GPIO47 from the processor can be used for IRDA or standard UARTS, so to meet the Card Engine pinout, the signals were connected to both sets of external pins.

Customers who want to be able to migrate to other Card Engines and use the UART functionality should use the B46, B47 pin locations. For customers who want to be able to migrate other card engine and use the IRDA functionality, they should use B30, B31.

B46,B47 should be sent to a level translator for normal RS232 translation.

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