LPC2478 how to initialize a SDRAM

haoch — Wed, 07 Feb 2018 07:18:12 GMT

Hello,i change a SDRAM of 32M to a SDRAM of 4M ,i rewrite the code as following ,but it still goes wrong, where else should i rewrite? TAHNKS

1.#define SDRAM_SIZE 0x00800000 //8M
//#define SDRAM_SIZE 0x02000000 // 32M

2. /* 64MB, 4Mx16, 4 banks, row=12, column=8 */
EMC_DYN_CFG0 = 0x00000280;
/* 256MB, 16Mx16, 4 banks, row=13, column=9 */

//EMC_DYN_CFG0 = 0x00000680;

3. dummy = *((volatile DWORD *)(SDRAM_BASE_ADDR | (0x33 << 11)));
// dummy = *((volatile DWORD *)(SDRAM_BASE_ADDR | (0x33 << 12))); //32M

Re: LPC2478 how to initialize a SDRAM

CarlosCasillas — Wed, 14 Feb 2018 01:35:27 GMT

Hi,

Have you ensured that both memories are physically connected to the same base address? On your rewritten definitions, you have changed SDRAM_SIZE, but SDRAM_BASE_ADDR seems to be the same (just modifying the shift count).

Hope this will be useful for you.

Best regards!

/Carlos

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topic Re: LPC2478 how to initialize a SDRAM in LPC Microcontrollers

LPC2478 how to initialize a SDRAM

Re: LPC2478 how to initialize a SDRAM