Hi all, I am working with the TI TUSB3200, trying to modify their example code for our own USB device. USB requires many tables which start with a length byte. I would like to use the sizeof operator to calculate this for me, as shown here:
byte code rictest[] = { sizeof(rictest), 1, 2 };
warning C198: sizeof returns 0
Hmm, I think you can make use of how Keil arranges/places variables in memory. They are not arranged in order of declaration, they are arranged alphabetically. So, if you declare: const unsigned char myarray[] = {1,2,3,4}; const unsigned int amyarraysize = sizeof(myarray) + 2/*include size of amyarraysize */); in one file, with no other declarations. amyarraysize will appear as the first in memory, followed by myarray. (Of cause myarray itself should no longer contain the size ...). Remember to move the pointer to amyarraysize, when copying. Now, Im not sure that it will always work, but I think so. If you really want to be sure, use the SECTIONS(?NC?YOURFILENAME?NCONST (addr)) to place it to a fixed place in memory Best regards Niels Sejersen
It is probably worth creating some validation code to make sure that things are located in memory in the order you wish. The symbol table manager uses a hash algorithm that may be changed in the future, so be careful using tricks like this. I'm not saying you shouldn't do this. I'm just saying that you should be careful. Jon
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