How to update application in bootloader many times ?

[khaoula_baala]

Hello,
 
I want to develop a CAN bootloader for MC9S12P
I can program and erase the P flash memory, but when i want to reprogram another application after executing the first one, the bootloader doesn't work as expected.

Here's my Start12.s :

I reprogram BootloaderKey @ 011300 in the application to 0x5aa5 and it works succesfully as shown in the picture

But when i execute application using the bootloader, the BootloaderKey doesn't change. So i cant jump back.

 .prm bootloader file : 

 .prm application file : 

N.B : I don't have access to any gpio pin in the board i'm using so I can't have a physical input to switch between bootloader and user application.

Thank's in advance for your help !

[dianabatrlova]

Hello,

I would like to apologize for the delay.

Unfortunately, I do not know where did you get the @ 011300 because the address of the D-flash is in the range below.

The Local address of D-Flash:
 0x0400 ~ 0x13FF
Global address of D-Flash:
0x4400 ~ 0x53FF

So, you should reprogram either local address 0x0C00 or global address 0x4C00

Please, refer to the attached memory map of the S12P MCU.

Also, the attached example shows how to program D-Flash.

Best Regards,

Diana