S12 / MagniV Microcontrollers中的主题 Re: MC9S12XDP512 - How to store two different startup code in a flash

MC9S12XDP512 - How to store two different startup code in a flash

sathish_K — Thu, 27 Sep 2007 16:31:46 GMT

Dear All,

I'm using MC9S12XDP512 microcontroller.
How I can store the two different startup code in a flash.

The first startup code used as a normal mode operation and the second startup code used for debugging (i.e. using this I'll modify the normal mode operation code in flash). How I can jump to the specified startup code.

please any one help....

Thanks,
Sathish.

--
Alban Edit: Please always include FSL Part Number in Message Subject line.

Message Edited by Alban on 2007-09-27 01:38 PM

Re: How to store two different startup code in a flash

Lundin — Thu, 27 Sep 2007 17:01:54 GMT

Why can't you use a compiler switch?

Re: How to store two different startup code in a flash

mke_et — Thu, 27 Sep 2007 17:10:28 GMT

I don't think I'm getting this.

Do you mean you want to test in your program and then decide how it boots? In that case, you have to 'split' your startup code. Figure out what you need to get the part started enough to do your test, like look for a pin held high or low and then make the decision which path to take.

But I still don't get this. Do you mean you want to use all templates and/or examples and do something custom? In that case, you're going to have to write your own startup code and figure out how and where to put your 'test'.

Re: MC9S12XDP512 - How to store two different startup code in a flash

ang — Thu, 27 Sep 2007 19:43:39 GMT

i understood like this

Among the two codes, one is a boot loader and this is used to flash the second code (application). If it is like that, you can write the start address of bootloader startup code at reset address (0xFFFE). And from the bootloader code, you can jump to the of application start address.

Regards

Ang

Re: MC9S12XDP512 - How to store two different startup code in a flash

JimDon — Thu, 27 Sep 2007 23:21:58 GMT

Ok, here is my take. He basically has two different places he wants to jump to on startup.

So you need some way to indicate which place to start. Assume you have a switch or jumper.

The startup vector is programmed to jump to some code that reads the jumper and jumps to the desired place.

Or am I jumping around too much :smileyhappy:.

Re: MC9S12XDP512 - How to store two different startup code in a flash

kef — Fri, 28 Sep 2007 13:55:05 GMT

satish.K,

If I understood your request, you want your software to know if MCU is running in debugging mode or in normal mode? Do you want your software to know if BDM pod is connected or not? If so then check MODE register. Normally, for debugging we are using special single chip mode (MODE==0). Normal single chip mpde is MODE==0x80. You can find MODE bits values for example from Figure 17-5. Mode Transition Diagram when MCU is Unsecured.

Re: MC9S12XDP512 - How to store two different startup code in a flash

sathish_K — Wed, 10 Oct 2007 12:36:14 GMT

Thanks for ur information and i have another one question.

How I can jump to specified startup code according with the MODE value(i.e. how I can jump to specified address in FLASH) and please give the sequence (in codewarrior).

Microcontroller : mc9s12xdp512

thanks,

Regards,

stathish.K

Re: MC9S12XDP512 - How to store two different startup code in a flash

Alban — Wed, 10 Oct 2007 13:26:11 GMT

Hello,

New Question = New Tread with appropriate subject line.

This thread is closed.

Regards,
Alban.