TMS320F28377D: Running CLA and CPU with different frequencies and data exchange between them.

UserHomeInit

Part Number: TMS320F28377D
Other Parts Discussed in Thread: C2000WARE, , TMS320F280049

Hello all,

We are using the CLA to compute a loop regulation, we managed to implement the loop control in the CAL but we still have some problems with the shared data between the CLA and CPU.

Our main loop is running at 35Khz and the CLA is running at 140KHz.

In the first configuration, we tried to initialize the CLA inputs values in the main interrupt service routine.

We remark that some variables are initialized in the main loop but CLA couldn't see them. We configure the CLA RAMs master for LS3 and LS4 and we use the ClatoRamMsg and CpuToClaMs sections, these memories are used to communicate data between CPU and CLA.

My question is what is the best way to change exchange data between CPU and CLA if they are not running at the same speed?

Thank you In advance,

S.Tarik

over 3 years ago

0 Ashwini Athalye over 3 years ago

TI__Expert 7695 points

Hi,

UserHomeInit said:
We remark that some variables are initialized in the main loop but CLA couldn't see them.

1. Please ensure that the variables are defined on the C28 side and are readable/wriatble from CLA task. To do this halt in the CLA task. Switch context to the C28, halt the C28 and make changes to the variable, now switch debug context to CLA and check if the updates are visible. If the updates are visible then we can confirm that there is no issue with the variable declaration and can move to step 2. If the updates are not visible, then the shared variables are likely not being allocated correctly. Please refer to the CLA examples in C2000Ware to see how shared variables are assigned to section in LSxRAM and shared across C28 and CLA.

2. Since both C28 and CLA are accessing the shared variable asynchronously. IPC may be used to synchronize access. Please refer to the guide below for tips and examples.

https://software-dl.ti.com/C2000/docs/C2000_Multicore_Development_User_Guide/intro.html

Thanks,

Ashwini

0 UserHomeInit over 3 years ago in reply to Ashwini Athalye

Expert 2185 points

Hello Ashwini,

I liked the IPC idea. I'll test your test strategy and I will be back if there is anything.

Does TI have any examples for Ipc between the CLA and CPU implemented on the TMS320F280049 or TMS320F28377D dsp in the C2000 package or control suite?

Thanks

0 Ashwini Athalye over 3 years ago in reply to UserHomeInit

TI__Expert 7695 points

We don't have any examples for F28004x and F28377x, but you can use the existing examples for F2838x as an reference.

Thanks,

Ashwini

0 UserHomeInit over 3 years ago in reply to Ashwini Athalye

Expert 2185 points

It's okay for me which on the 28338x?

could you share the link, please?

+1 Ashwini Athalye over 3 years ago in reply to UserHomeInit

TI__Expert 7695 points

Please refer to the Multi-core development guide for examples: https://software-dl.ti.com/C2000/docs/C2000_Multicore_Development_User_Guide/intro.html

Thanks,
Ashwini

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TMS320F28377D: Running CLA and CPU with different frequencies and data exchange between them.