Activation UART4 in AM3517

Hello James,

1) the base address for UART4 is 0x4809 E000.   There is an issue in the Technical Reference Manual that shows the base address for each of the registers.  You wil need to add the offset to the base address to get the correct address. 

2)  IRQ for UART4 is 84

3) fck is enabled on bit 23 of PRCM.CM_FCLKEN1_CORE

4) you can find the registers for UART4 in the Technical Reference Manual section 14.6.  I am still working to get the base address issue mentioned above fixed, but here is the link to the latest manual: http://www.ti.com/litv/pdf/sprugr0b

Dear Jeff

See below your posting to Jennier. It is a little bit confused. In the main text you said base address is 0x4809e000, but In your example on MCR_REG, you use 0x4806E000 instead of 4809E000. Please confirm that 0x4809E000 is correct.

Second,  I knew that new TRM is there, but when I access one of registers, fault exception happens. So, I am trying to turn UART4 on.

Is there any registers to turn it on except fck and ick ? Did you have a report someone use UART4 successfully?

Thanks in advance

James

Hello Jennifer,

I see what you are talking about now.  In the actual register description section (14.6.2) where it shows the Physical address of UART1, 2, 3, and 4 it always shows UART4 as it's base address (0x4809 E000) instead of the true physical address.  I will work to get this fixed in the next release of the TRM. 

The Address offset is the same for all UARTs so you can just take and add the offset of the registers to the base address.  For example:  The MCR_REG (section 14.6.2.10) has an address offset of 0x010. 
UART1 = 0x4806 A010
UART2 = 0x4806 C010
UART3 = 0x4902 0010
UART4 = 0x4806 E000 + 0x010 = 0x4806 E010

Best regards,
Jeff

Hi Jeff

Thank you for update; it helps, but could you double check for your link.

oops, that is a TI internal link.  I will check to see if I can release the sample code that is there and if so, I will post it here.

hi freinds!!

can you me tell in which register do you store the ISR address.

Please let me know ......

i have the following code for Irq.c

#include "am35xx.h"
#include "types.h"
#include "irq.h"



UL32 install_irq( UL32 IntNumber, void *HandlerAddr, UL32 Priority )
{

        UL32 *vect_addr;
        UL32 *vect_prio;

    if(IntNumber <= 0  && IntNumber >= 31)
    {

     
     INTCPS_MIRC0 = 1 << IntNumber ;                                     /* Disable Interrupt */

    }

    else if(IntNumber <= 32  && IntNumber >= 63)

        {
           

            INTCPS_MIRC1 = 1 << (31 - IntNumber);                    /* Disable Interrupt */


        }

        else if(IntNumber <= 64  && IntNumber >= 95)                /* Disable Interrupt */

        {

   
               
           INTCPS_MIRC2 = 1 << (63 - IntNumber);                        /* Disacble Interrupt */

        }

        if ( IntNumber >= MAX_NUM_INT )
        {
       
        return (FALSE);
       
        }
        else
        {

      

       vect_addr = (UL32* )(which register + (what index addr * 4));  <----             i need help at this statement.

        vect_prio = (UL32 *)(ILRM_BASE_ADDR + (IntNumber * 4));
        *vect_prio = Priority;
        *vect_addr = (void)Timer0Handler;
        // code to enable interrupt
        return(TRUE);
        }


   return (0);
}

http://e2e.ti.com/support/dsp/sitara_arm174_microprocessors/f/416/p/106085/373798.aspx#373798

Link for .h file