Can't get clock data on CKO1/PTB10.

[johnclarke]

Hello,

I have a SVF321R3CKU2 that I would like to measure some of the clock speeds using CKO1 on PTB10.  I have configured the CCM_CCOSR  register to enable CKO1, set the divisor to /4 and selected the A5 Core for the output.  With the current clock setting the A% clock should be running at 264 MHz.  I have also configured the IOMUXC for PTB10 to select the CKO1 ALT6.  I am using a debugger and verified the following settings:

PTB10: 0x005028C6

MUX_MODE: CKO1

SPEED: Medium – 100MHZ

SRE: Fast

ODE: Disabled

HYS: Disabled

DSE: 50 Ohm/80 Ohm

PUS: 100 kOhm Pull Down

PKE: Disabled

PUE: Pull

OBE: Enabled

IBE: Disabled

CCM_CCOSR: 0x000004FD

CKO1_EN: Enabled

CKO1_DIV: /4

CKO1_SEL: CA5 core clock

However I get no output on PTB10/CKO1.  Am I missing a configuration item?  Any help would be appreciated.

Thanks you,

John Clarke

Message was edited by: John Clarke Just realized I labeled the registers wrong in the initial post, sorry for any confusion.

[johnclarke · Accepted solution]

Thanks to Chris at Freescale I have a solution to my question.

I feel a bit foolish and therefore will explain my findings.

The settings in the debugger say the following for PTB10 set to 0x006028C6 (setting from Chris at Freescale):

Note that for MUX_MODE it says Reserved.  This is really CKO1!

The settings in the debugger say the following for PTB10 set to 0x005028C6 (settings I was using):

Note that the MUX_MODE says CKO1, it's not, it's really VIU_DE.

The Lauterbach debugger I am using incorrectly labeled the MUX_MODE and I believed it.

Should have believed the data sheet and NOT the tool.

Regards,

John Clarke

[alejandrolozan1]

Thanks Jhon for sharing your findings!!