TMS320F28377S: Size of enum on CPU and CLA

user5341576

Part Number: TMS320F28377S

Hi there!

I have a problem with the different sizes of enum on the CPU and CLA on C2000 28377S. It is similar to this post: https://e2e.ti.com/support/tools/ccs/f/81/t/514189

I have an enumeration, which I declare in a shared file. Then I have a state machine running on the CPU, which changes the value of this enumeration. And then I use some If-statement in the control code on the CLA to execute the correct code depending on the value of the enum-variable.

Can someone please give me an example how to equalize the size of enum on CPU and CLA?

< //// Shared file
enum enum_test{
    state1 = 0,
    state2 = 1,
};
extern volatile enum enum_test state;

//// main.c
state = state1;

/// CLA
if(state == state1)
{}
else if (state == state2)
{}
>

Best regards

over 6 years ago

0 EK over 6 years ago

Expert 2520 points

Since CPU and CLA have different size of type int, I think you should use type which has the same width on both, either short or long, and anonymous enum with enum value with some unique prefix to distinguish from other vars or constants:
enum{ 
    stState1 = 0, 
    stState2 = 1, 
}; 
extern volatile short state; 
//// main.c 
state = stState1; 
/// CLA 
if(state == stState1) 
{} 
else if (state == stState2) 
{} 

0 user5341576 over 6 years ago in reply to EK

Prodigy 150 points

Hi EK,

Thank you. In princple your suggestions works and creates the behaviour I want.

But I would like to have the variable state as an enumeration.

0 user5341576 over 6 years ago in reply to user5341576

Prodigy 150 points

I found the solution by using typedef union{} similar to the pointer approach!

0 EK over 6 years ago in reply to user5341576

Expert 2520 points

I would try as well adding some unused enum value which doesn't fit 16bits:

enum enum_test{

state1 = 0,

state2 = 1,

__dummybig = 300000,

};

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TMS320F28377S: Size of enum on CPU and CLA