pinmux UART2

Autonomous Machines Jetson & Embedded Systems Jetson TK1
1

Hi All,
On the TK1 TRM page 306 & 307, SFIO2=UARTA for TXD2 & RXD2 !!!
Is it an errata (SFIO2=UARTB) ?
If i want to use UART2/UARTB (only TXD2/RXD2) in “normal mode” (not IR mode) what is the right pinmux config ?
Greg

2

Hi, grp62,

I have tested with below two methods and measure the signal in J3A2/pin68 (UART2_TXD) to be able toggle by scope.
To pick up ethier one should be work without any pinmux modification.

1.modify the command line in /boot/extlinux/extlinux.conf
debug_uartport=lsport,0

2.hard code the debug_port_id arch/arm/mach-tegra/board-common.c
50 int uart_console_debug_init(int default_debug_port)
51 {
52 int debug_port_id;
53
54 debug_port_id = 1;//get_tegra_uart_debug_port_id();

3

Thanks for your feedback.
In page 306 & 307 we can read that the reset value for bit[1…0] of the PINMUX_AUX_UART2_TXD_0
& PINMUX_AUX_UART2_RXD_0 registers are 0b00 so UART2_TXD & UART2_TXD are configured by default in IRDA mode after a reset.
If i want to have the UART functionality, i have to write 0b10 in bit[1.0].
What i mean is that in the documentation we should read UARTB and not UARTA.