TMS320C6748: Configuring the PLL

Alan Jayson

Prodigy 90 points

Part Number: TMS320C6748

I'm looking to config the PLL:

OSC Frequency: 20 MHz
CPU: 300 MHz
EMIFA: 100 MHz
DDR2: 200 MHz

I've installed Starterware. I don't see any examples (The example for GPIO works fine).

If someone could point me in the right direction that would be great.

Alan

over 4 years ago

0 Sahin Okur over 4 years ago

TI__Mastermind 27355 points

Hi Alan,

Please see the following.

Programming PLL Controllers on OMAPL1x8/C674x/AM18xx

Are you loading via CCS or bootloader? If using CCS, the PLL is typically configured in the GEL file.

Also, please note Starterware support is legacy software that is no longer maintained and support for it may be limited. If this is new development, we recommend starting with Processor SDK for the newest features, bug fixes, and support.

If you have any questions please let us know.

Best,
Sahin

0 Alan Jayson over 4 years ago in reply to Sahin Okur

Prodigy 90 points

I'm running bare metal so the SDK is not for me.

New product (was using TMS320VC33-150, ran 5 sets of iir filters in real time), we are running 3 sets of iir filters in real time (20 kHz), interrupted from an FPGA.

Alan

0 Sahin Okur over 4 years ago in reply to Alan Jayson

TI__Mastermind 27355 points

Hi Alan,

Understood, thanks for the info.

In Starterware, the GEL files are located under the tools/gel/ folder. You can plug the C6748 GEL file into your target configuration file in CCS and it will run the GEL file and initialize the PLLs when connecting to the core.

If you need further guidance on this please let me know.

The following E2E thread may help as well.

https://e2e.ti.com/support/processors/f/791/t/779324

Best,
Sahin

0 Alan Jayson over 4 years ago in reply to Sahin Okur

Prodigy 90 points

I’m going to stay away from GEL since it doesn’t help at the end of the design.
I’ll look for the address to control the PLL from C code.

Thanks,
Alan

0 Mukul Bhatnagar over 4 years ago in reply to Alan Jayson

TI__Guru* 78305 points

Alan

You can stay away from GEL file, as we agree that for end design you will need all that code as part of your application code.

Few things to note

1) The GEL file is a good reference how and what to program the PLLs to get the desired frequency (which is what I believe was your original query).

2) When you are in finally ready to implement this in the end of the design, you should also look at the boot loader application note, the ROM can set some of these values for you. See details in the AISGEN section in the following application note

http://www.ti.com/lit/an/spraat2f/spraat2f.pdf

0 Sahin Okur over 4 years ago in reply to Alan Jayson

TI__Mastermind 27355 points

Alan,

I'm going to close this thread and mark it as resolved for now. If you have any updates feel free to post a reply here to re-open the thread or create a new thread by pressing the "+ Ask a related question" button at the top if this thread has locked due to time.

Regards,
Sahin

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TMS320C6748: Configuring the PLL