Hi, expert:
I have two questions about using MPC5604 platform.
Question 1(about volatile):
I used keyword "volatile" to define a const. The code is shown below:
#pragma push
#pragma section code_type ".user_data"
volatile const uint8 COMBINE_FLAG = 0x1;#pragma pop
If I only define this const and don't use it. The const will be optimized. The size of the section ".user_data" is 0.
If I use the const, For example:
uint8 read_flag;
read_flag = COMBINE_FLAG;
The const will have address. The size of the section "user_data" is greater than 0.
The Global optimizations is:
Why the keyword "volatile" and "const" have no effect?
Question 2(about fixed address):
In 9S12 platform, I can figure the fixed address in coding:
const uint8 COMBINE_FLAG @0xEF00;
But the "@" can't be used in MPC5604 platform. When I compile the code with codewarrior, the compiler tell me:
Besides using "pragma" keyword, How can I allocate a const in a fixed address?
Thanks.
Bryce
2017-12-12