CCS/TMS320C5515: 8192 points Twiddle Table

Matteo Nini

Prodigy 75 points

Part Number: TMS320C5515

Tool/software: Code Composer Studio

Hi,

I'm trying to do an HWAFFT of 8192 points, and I need to create the twiddle vector of 4096 imaginary values.

From what I saw in the 4096pts example they are in a certain order but I don't understand what order.

If someone have more pieces of information please post.

Thanks everyone

over 6 years ago

0 Cvetolin Shulev-XID over 6 years ago

TI__Guru 65405 points

Hi Matteo,

Please see the updates in this thread:
e2e.ti.com/.../2866325

Regards,
Tsvetolin Shulev

0 Matteo Nini over 6 years ago in reply to Cvetolin Shulev-XID

Prodigy 75 points

Yeah...well, I posted that thread, so....

0 Matteo Nini over 6 years ago in reply to Matteo Nini

Prodigy 75 points

I'm posting again now because finally after two weeks I've resolved the issue.
For everyone who have the same problem: don't bother downloading twid4096.asm because it's incorrect.
The values are in bit-reverse order, but it's wrong for the code in test.c.
If you want to run a FFT on a TMS320C5515 (or similar processor) download test.c and test.cmd, then create a header file where you manually put the values in the order MATLAB create them. Don't make them bit-reversed!
If you want to download test.c and test.cmd look in this thread: e2e.ti.com/.../953086
If you want to create the Twiddle Factor via MatLab I used the code from this thread: e2e.ti.com/.../663403

Processors

Processors forum

CCS/TMS320C5515: 8192 points Twiddle Table