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sigh, I have a bootloader working!

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This commit is contained in:
David Welch
2012-05-27 02:31:05 -04:00
parent d69e19201f
commit c44c1146ea
11 changed files with 931 additions and 0 deletions
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57
bootloader01/blinker.c Normal file
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//-------------------------------------------------------------------------
//-------------------------------------------------------------------------
extern void PUT32 ( unsigned int, unsigned int );
extern unsigned int GET32 ( unsigned int );
extern void dummy ( unsigned int );
#define ARM_TIMER_LOD 0x2000B400
#define ARM_TIMER_VAL 0x2000B404
#define ARM_TIMER_CTL 0x2000B408
#define ARM_TIMER_DIV 0x2000B41C
#define ARM_TIMER_CNT 0x2000B420
#define SYSTIMERCLO 0x20003004
#define GPFSEL1 0x20200004
#define GPSET0 0x2020001C
#define GPCLR0 0x20200028
#define TIMEOUT 1000000
//-------------------------------------------------------------------------
int notmain ( void )
{
unsigned int ra;
unsigned int rb;
ra=GET32(GPFSEL1);
ra&=~(7<<18);
ra|=1<<18;
PUT32(GPFSEL1,ra);
PUT32(ARM_TIMER_CTL,0x00F90000);
PUT32(ARM_TIMER_CTL,0x00F90200);
rb=GET32(ARM_TIMER_CNT);
while(1)
{
PUT32(GPSET0,1<<16);
while(1)
{
ra=GET32(ARM_TIMER_CNT);
if((ra-rb)>=TIMEOUT) break;
}
rb+=TIMEOUT;
PUT32(GPCLR0,1<<16);
while(1)
{
ra=GET32(ARM_TIMER_CNT);
if((ra-rb)>=TIMEOUT) break;
}
rb+=TIMEOUT;
}
return(0);
}
//-------------------------------------------------------------------------
//-------------------------------------------------------------------------