LPC1875 SDRAM Reading infinitely;CPU locked up

sanjaymurthy — Fri, 03 Feb 2017 15:01:36 GMT

Hi,

I'm working on a custom board which uses LPC1857 cortex-M3 processor. The SDRAM AS4C16M16SA (4M word x 16-bit x 4-bank) connected to DYCS1. The SDRAM initliazation looks ok on the scope. Also SDRAM write seems to be ok. Below in the SDRAM/Controller configuration and intialization code attached.

While reading a byte until address 0x30000000 to 0x30000003 everything seems ok and I think it is because of the buffer. After that porocessor locks up and goes for infinite read. I would appreciate if anybody could help with their ideas.

testing method:

#define SDRAM_BASE_ADDR (0x30000000 | 0x3)

  //write
  add = (uint8_t *)(SDRAM_BASE_ADDR );
  for (i=0;i<66;i++)
{
  *add = num1 ;
  //num1++;
  add++;

}
blink(led1);


//read
   add = (uint8_t *)(SDRAM_BASE_ADDR );
  for (i=0;i<1i++)
  {
   val1[i] = *add;
   add++;
  }
while (1) {blink(led2);}

-Using Keil MDK Pro and Jlink debug adapter

Thanks,

Sanjay

Original Attachment has been moved to: sdram-init.txt.zip

Re: LPC1875 SDRAM Reading infinitely;CPU locked up

sanjaymurthy — Tue, 07 Feb 2017 12:33:23 GMT

Just in case if anyone come around this problem it was the clock. I had configured just Clk1.

Sanjay

LPC MicrocontrollersのトピックLPC1875 SDRAM Reading infinitely;CPU locked up

LPC1875 SDRAM Reading infinitely;CPU locked up

Re: LPC1875 SDRAM Reading infinitely;CPU locked up