TMS320F28388D: Configuring GPIOs, CLB-XBARs, and Output-XBARs on CPU2 via SysConfig

Wilko

The XBAR registers are only accessible from CPU1 and hence these configurations appear only in the CPU1 context.

Best Regards

Siddharth

Hi Siddharth,

I just wanted to clarify:
If I am using the CLB on CPU2, does this mean I cannot use the CLB XBARs at all?
Or are the CLB XBARs simply assigned to CPU1 for configuration, but they can still route signals to and from the CLB modules assigned to CPU2?

Best regards,

Wilko

Hi,

CPU1 should configure the CLB XBARs and can be used by CPU2

Best Regards

Siddharth 

Hi Siddharth,

Thank you for your response.

I wanted to ask if there’s anything specific I need to consider when configuring the CLB OutputXBAR via a CLB module running on CPU2.
In my tests, I was able to successfully drive the CLB OutputXBAR using a CLB module on CPU1. However, after switching to an identical CLB configuration on CPU2, the output no longer seems to work.

Is there any known limitation or extra step required when using the CLB OutputXBAR from CPU2?

Best regards,

Wilko

Wilko

I don't think any other step is required .

The CLB config can be moved to CPU2  but XBAR config has to be in CPU1 only. 

Best Regards

Siddharth

Hi Siddharth,

I have now taken the example project: "empty_c28x_dual_sysconfig".

I have implemented the CLB OutputXbar and a CLB on CPU1 where I toggle a GPIO.

Everything works. When I implement the same CLB on CPU2 and do the exact same initialisation in the main of CPU2 and connect this CLB to the CLB OutputXbar then it does not work anymore. 

Could you confirm, that this works on your side ?

Since I am not sure how to break this problem down any further. 

Best Regards,

Hi Siddharth,

I’ve attached a minimal example of the issue as a ZIP file.

You can run the code using the included .out files, or build your own using the provided project files.

In the SysConfig view, you’ll see that one CLB is configured on CPU1 and another on CPU2.

To observe the output toggle, simply change the CLB OutputXbar source signal from CLB2.OUT4 to CLB1.OUT4.

Let me know if you need anything else.

Best regards,

Wilko

CLB Test CPU1-CPU2.zip

Siddharth Deshpande 

Did you get the chance to test my minimal project on your side ?

Could you find my error ?

Regards,

Wilko

Can anyone please confirm or deny the following statement ?

Siddharth Deshpande said:

Wilko

I don't think any other step is required .

The CLB config can be moved to CPU2  but XBAR config has to be in CPU1 only. 

Best Regards

Siddharth

I have been waiting for confirmation for about a month, as I need to decide whether I must move the entire CLB configuration to CPU1, or only the XBAR configuration.

As mentioned earlier, I have been unable to get the CLB running on CPU2, even in the most minimal example.

Regards,

Wilko

Since I haven’t received a response for several months, I have to assume that CLB configuration cannot be performed by CPU2.

This means we are now forced to move the entire CLB configuration to CPU1. Unfortunately, this is a significant drawback for us, but at some point, we need to move forward.

Thank you for your support nonetheless.

Regards,

Wilko