set Tiva C series 80MHZ

Hello Majid

On TIVAWare 2.1.0 , there is an issue with the SysCtlClockGet which would return 66MHz. Please use 80MHz for computation.

Regards

Amit

Hi Amit,

But the real clock is 66Mhz, I need to set it on 80Mhz, 

thanks

Hello Majid,

Can you please respond to the following queries

1. Which TIVAWare release are you using?

2. How are you measuring the Clock?

3. Is this a custom board or a LaunchPad board?

4. Can you read the SYSCTL.DID0, SYSCTL,DC1, SYSCTL.RCC and SYSCTL.RCC2 registers and send the value?

Regards

Amit

Hi

TivaWare_C_Series-2.1.0.12573

I have used SysCtlClockSet(); and PWM,

Also i am testing it on Launchpad board Tiva c series TM4C123GM

SYSCTL_DID0 0x18050101 Device Identification 0 [Memory Mapped]

SYSCTL_DC1 0x13332FFF Device Capabilities 1 [Memory Mapped]

SYSCTL_RCC 0x01400540 Run-Mode Clock Configuration [Memory Mapped]

SYSCTL_RCC2 0xC1004000 Run-Mode Clock Configuration 2 [Memory Mapped]

thanks

Hello Majdi,

I believe the SYSMINDIV setting in the SYSCTL.DC1 register (bits 15:12 with value 2) is putting a limiter on the clock frequency.

How are you measuring the clock frequency, is still not clear to me?

Regards

Amit

I have used SysCtlClockGet(); comment to see the clock in debugging mode.

Hello Majid,

I think that is what I mentioned in my first post-reply. There is a bug in the SW implementation of SysCtlClockGet because of which it would return 66MHz. Instead of using the return value of the function SysCtlClockGet use 80MHz as the variable assigment

Instead of

ui32SysClock = SysCtlClockGet();

use

ui32SysClock = 80000000;

Regards

Amit

Hi Amit,

Thanks for your help,

the problem was  SysCtlClockGet(). I checked the frequency in PWM and it was 80MHz.

Thanks again

majid