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Re: about MMU Problem(include problem.h)


Hi 

As I understand in second case you don't have correct placed mmu_table. When 
you start up MMU - it is took dummy data instead translation table.

case 1:
        ldr	r0, =mmu_table
	add     r2, r0, #0x4000     	// End of tables
	mov	r1, #0x00000000
	orr	r1, r1, #0x4000		// RAM tables

	// everything can go as-is
    1:
	ldr	r3, [r0], #4
	str	r3, [r1], #4
	cmp	r0, r2
	bne	1b
you copy from mmu_table to address 0x0 this table.
case 2:
        mov	r1, #0x00000000
	orr	r1, r1, #0x4000		// RAM tables
	add     r2, r1, #0x4000     	// End of tables

	// First clear table
	mov	r0, #0
    1:
	str	r0, [r1], #4
	cmp	r1, r2
	bne	1b
you copy memory from address 0x4000 to address 0x0. Are you sure if on address 
0x4000 is mmu_table????

Best Regards,
jerzy

 
On Wednesday 29 December 2004 07:22, g723 wrote:

> Hi,
>    Follow the attach file,if i use case 1 to run   this code,it's ok.
>    When i use case 2 to run,the code will fail
>    when enable mmu function.
>    Can you tell me what's wrong when trans to mmu table or any file must be
> set ?

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