Ok, have not been exact enough in description.
Want to build second application UART port onto a TWR-PROTO board. This second UART is TTL-UART, so do not need RS-232 PHY. TWR is populated with TWR-K70 cpu board, TWR-SER board and TWR-PROTO board. May like to have TWR-LCD too, but can live without it. Can omit TWR-SER, as 'printf' could be catched via USB too.
Need advice, which UART port of cpu board to use (would prefer UART0).
Summary for TWR-K70F120M cpu board (please tell, if wrong):
There are 4 possible UART(-Rx-Tx) default pin pairs on TWR-ELEV boards (I call them "twre_UARTx" in contrast to "cpu_UARTx"):
"twre_UART0" is connected to "cpu_UART2"
"twre_UART1" is connected to "cpu_UART3" (if 0 Ohm bridges R134/R135 would be placed)
"twer_UART2" is not connected to cpu
"twer_UART3" is not connected to cpu.
Prefer using "cpu_UART0". Possible TWR-ELEV pins for "cpu_UART0_RX/TX" are:
PTF17/PTF18
PTA1/PTA2
PTA15/PTA16
PTB16/PTB17
PTD6/PTD7.
Think that PTF17/PTF18 (secondary connector D53/D54) is best to catch "cpu_UART0_RX/TX" on a TWR-PROTO board.
Seems to have lowest conflict potential with other TWR boards. Do you agree?
Best regards, Juergen.