Help with SCI and F28335

charles saperstein

Expert 1445 points

I'm familiar with the F28069 and am now working on a project

What is the baud rate of the sci_loopback sample?

The F28069 had a function for selecting the internal oscillator (IntOsclSel) I do not see that with this processor?

what is the LPSCLK set to?

over 8 years ago

0 Brett Larimore over 8 years ago

TI__Guru 57255 points

Hi Charles,

First of all, unlike the F28069, the F28335 does not have any zero-pin internal oscillators. The F28335 can only be clocked with the help of some type of external circuitry - either a crystal or an external source.

As a result, its hard to say what any of these clocks or the baud is because it is very dependent on your crystal/source.

However, the F28335 controlCARD has a 30MHz crystal on it. The examples expect this and configure SYSCLK such that it is 150MHz. LSPCLK is then, in this code, set as SYSCLK/4 (LOSPCP).

Hopefully this helps some!

Thank you,
Brett

0 Gautam Iyer over 8 years ago

Guru 192875 points

Hi Chuck,

Adding more to Brett, if you're using TI's experimeter kit that consist of F28335 controlCard then the sample code is designed for achieving 9600 baudrate. Else it depends on SYSCLK.

Regards,
Gautam

0 charles saperstein over 8 years ago in reply to Brett Larimore

Expert 1445 points

Thanks. Set SCILBAUD to 0xF3 (199200). Now communication is good.

0 Gautam Iyer over 8 years ago in reply to charles saperstein

Guru 192875 points

Great!

Goodluck & Regards,
Gautam

0 charles saperstein over 8 years ago in reply to charles saperstein

Expert 1445 points

19,200 baud.

0 Gautam Iyer over 8 years ago in reply to charles saperstein

Guru 192875 points

Got that previously! :)

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Help with SCI and F28335