LPC932 secutiry bits

[Jensen Hu]

HI :

I developed my application on MCB900, tested and worked well. However, when I set security bits on Flash Magic and reporgram LPC932, the program does not function correctly, any idea why ?
Any comments will be appreciated.

Thanks

Jensen

[Andy Ayre]

Can you describe more what happens? Which security bits did you set? How does your program behave differently? What happens if you do a full erase and repgram without setting the security bits?

[Jensen Hu]

Hi Andy:

My program size is about 4550. Lpc 932 is connected to a wireless moudle. When wireless moudle receive a valid packet, lpc932 begin to process it and send received information to the host pc vie RS232

I always check the Erase all fresh box when I transfer the program.

If I set
Block 0 bit 0, bit 1
Block 1 bit 0, bit 1
Block 2 bit 0, bit 1
Block 3 bit 0, bit 1

The program can only process one packet sent from the wireless moudle. Any additional packets will not be processed.

At this time I can only set

Block 0 bit 0
Block 4 bit 0

In this way the program will function normally.

If I set bit 0 on Block 2 and Block 3. The program will not work.

Any bit 1 set will make program not functional.

I have also tried Fill unused flash and generated checksums, they don't seem to matter.

Thanks

Jensen Hu

[Andy Ayre]

Setting bit 0 stops MOVC from returning correct data. Your code will use that instruction if you try to read constants from code memory, for example. Bit 1 stops programming and erasing, and I think that would only be a problem if you are using IAP routines.

You need to debug your code to find out exactly where it is failing. Once you have done that reduce your code to the point where it works or until you have the simplist possible program that reproduces the problem. Once you are at that point, I suggest posting your problem to the forum at 8052.com, but be sure to include everything that you have tried, all observations you have made, etc.

[Jensen Hu]

Hi Andy:

The reason I want to set the scurity bits is to prevent people from copying the program. What are the scurity bits I should set in order to achieve this purpose ?

Thanks

Jensen Hu

[Andy Ayre]

The user manual available from www.philipsmcu.com will give you a detailed description of the security bits. If I were to answer here I would simply be copying from the user manual.