8-bit Microcontrollers中的主题 Re: Serial number inclusion

Serial number inclusion

UtopiaTim — Tue, 15 Jul 2008 20:50:59 GMT

Hi Folks,

The project that I am currently working on requires a serial number

to be transferred out of the unit via USB. All of the USB stuff is done, and

a serial number that I place in RAM using the following code works great.

unsigned char serial_number[5] = {0x00,0x00,0x03,0xe9,0xf3};

I know that P&E has a program that I can use to serialize the unit, but I am

at a loss as how to set up the location in flash. It would have to be a

'hard wired' location that I know the actual addresses of.

How can I set that up in C?

Thanks,

Tim

Re: Serial number inclusion

Ake — Wed, 16 Jul 2008 14:01:26 GMT

Hi,

In CodeWarrior's version of C, you write

const unsigned char serial_number[5] = {0x00,0x00,0x03,0xe9,0xf3};

to get the string in readonly memoory.

I am not sure if this can be done with the P&E C-compiler.

Regards,

Ake

Re: Serial number inclusion

bigmac — Wed, 16 Jul 2008 21:46:16 GMT

Hello Tim,

I presume you are actually using the CW compiler. If so, the following method seems to produce the expected result.

Firstly you need to define a specific segment within the .PRM file to contain the serial number value, that is not used by any other code. For example, the following would be suitable for a QG8 device (obviously not the device you are using) -

SER_NUM = READ_ONLY 0xE000 TO 0xE00F;
ROM = READ_ONLY 0xE010 TO 0xFFAD;

The serial number array could then be defined as follows -

const unsigned char serial_number[5] @0xE000 = {0x00,0x00,0x03,0xe9,0xf3};

Regards,

Mac

Re: Serial number inclusion

UtopiaTim — Thu, 17 Jul 2008 02:53:46 GMT

Hi Mac,

Thanks for the info.

I set up the .PRM file with the addresses that I wanted to be able to store

the data to, but under the definitions that you suggested, I don't want the

compiler to pre-assign values, I want the P&E serializer program to be able

to write directly to the flash with the serial number they provide (through their

program).

Of course, I want to be able to reference it in the software, perhaps I only

need to do the following??

const unsigned char serial_number[5] @ 0xFF00;

Thanks,

Tim

Re: Serial number inclusion

bigmac — Thu, 17 Jul 2008 07:46:07 GMT

Hello Tim,

Using FCS for testing purposes, it would appear that the compiler does initialise each element of the array to 0x00 by default - not what you require. You might try explicit initialisation to a value of 0xFF, the unprogrammed flash state, and see if this can be made to work in conjunction with the serialize utility.

Regards,

Mac

Re: Serial number inclusion

CompilerGuru — Thu, 29 Oct 2020 09:21:36 GMT

This should work:

Code:

unsigned char serial_number[5] @ 0xFF00;

or the ANSI-C version:

Code:

#define serial_number (*(const unsigned char*)0xFF00)

Daniel

Re: Serial number inclusion

UtopiaTim — Thu, 17 Jul 2008 12:29:58 GMT

Hi Mac & all,

That's how I did it - initialized it to ff's, & then the P&E standalone serialize program

could program those ff's to the new serial number. (given the absolute address in memory, etc)

Thanks again to all!

Tim