MPC5744P Jump problem

xiaobozheng — Wed, 26 Oct 2016 03:26:56 GMT

our project has two independent programs (bootloader and application program), our bootloader will loading application program form mmc card and programming it to the chip rom memory. and then jump to it start addresss.

but we found if our bootloader init the chip registers and then jump to application program start addresss, an error will happen when application program running.

our application program still need init the chip same registers again with different values (for example : clock, interrupt , peripheral..),

int main()

{ /*this is our bootloader main function, when bootloader finished and jump to application program , the application program will create an error and it can not work*/

Sys_Mode_Drun();

ShutDownSelfTest();

Hardware_Init();

C55_Flash_Init();

C55_Eeprom_Init();

_bootloader(NULL);

C55_Flash_SetLock();

/*jump address :0x01000020*/

__asm("e_lis r3, 0x0100");

__asm("e_or2i r3, 0x0020");

__asm("se_mtctr r3");

__asm("se_bctr");

while(1);

}

According to our test , if our bootloader do not init the chip registers, for example: in our main function we do nothing just only jump to application program start address and running, there is no error, application program can working normaly.

int main()

{/* this is our bootloader main function ,we do nothing ,just jump to application program , the appl can working normoaly* /

/*jump address :0x01000020*/

__asm("e_lis r3, 0x0100");

__asm("e_or2i r3, 0x0020");

__asm("se_mtctr r3");

__asm("se_bctr");

while(1);

}

Why this is happen? And how can we fix it ? thanks !

Is there any points we need to know when one program jump to another program on the same chip ?

Re: MPC5744P Jump problem

lukaszadrapa — Wed, 26 Oct 2016 08:13:39 GMT

Hi,

I wrote something similar here:

https://community.nxp.com/message/605376?commentID=605376#comment-605376

"In this case, it is necessary to disabled all interrupts and put all the modules to default reset state. Or the user application must be aware that it is possible that modules are not necessarily in reset state."

I guess that this is the source of troubles...

Regards,

Lukas

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MPC5744P Jump problem

Re: MPC5744P Jump problem