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Turns out that CONTROL_CONF_UART_RXD(n) and  CONTROL_CONF_UART_TXD(n)   don't give the correct offset for UART2 and UART3. Have to use the offsets

CONTROL_CONF_MII1_TXCLK

CONTROL_CONF_MII1_RXCLK

CONTROL_CONF_MII1_RXD2

CONTROL_CONF_MII1_RXD3

Hello Brad,

I see that you have targeted the right functions to change to port to UART2 instance. I suppose you are referring to these two files:

• utils/uartStdio.c
• platform/evmAM335x/uartConsole.c

 The changes that need to be made are:

• UART0ModuleClkConfig:

This function has to be ported to UART2 instance. Note that UART0 is in Wake-up domain and  UART2 is in Peripheral domain. You have to refer to Control Module chapter in AM335x TRM to find the registers relevant to UART2 and set the appropriate bits. 

• UARTPinMuxSetup:

As it is obvious, the StaterWare package has not provided the code to pin multiplex UART2 pins. The UART2 pins namely UART2_TXD and UART2_RXD are available on different pins and in different Mux modes. The offset addresses of each of these pins are different.

To give you an example:

‘uart2_rxd_mux2’  and  ‘uart2_txd_mux2’ pins are available with offset addresses 0x0900 and 0x0904 respectively. The multiplexing mode is Mode3.

‘uart2_rxd_mux1’ and ‘uart2_txd_mux1’ pins are available with offset addresses 0x090C and 0x0910 respectively. The multiplexing mode is Mode6.

 You have carefully do the correct pin multiplexing.

• UARTStdioInitExpClk() :

This function need not be changed. The file ‘uartConsole.c’ mentioned above uses the UART0 Base address for the various UART functions.

#define UART_CONSOLE_BASE                    (SOC_UART_0_REGS)

You have to change the right-hand macro to SOC_UART_2_REGS to use UART2 registers.

Please revert if you have any queries.

Thanks and Regards.

Gurudutt.