IPUv3 How to change DISP_CLK waveform

norishinozaki — Tue, 21 Jun 2016 07:10:06 GMT

Hello,

I'm using IPUv3 in i.MX51 and I need to change DISP_CLK waveform to interface to a LCD.

There are four related settings for this.

DI0_DISP_CLK_UP

DI0_DISP_CLK_DOWN

DI0_DISP_CLK_OFFSET

DI0_DISP_CLK_PERIOD

I'm using WinCE and I can only change UP and DOWN parameters, but tmebase doesn't work and DISP_CLK doesn't chage.

How can I initiate timebase?

Do I need to set OFFSET and PERIOD as well?

Are there any registers to consider?

BR,

N.S

Re: IPUv3 How to change DISP_CLK waveform

Yuri — Tue, 21 Jun 2016 07:55:59 GMT

Hello,

As for display clock, please look at section 42.3.10.3 (Timing generator) of the

i.MX51 Reference Manual.

The base signals look as a pulse ___|----|____

This pulse is defined by length (PERIOD), first edge location (UP) and second

edge location (DOWN).

Basically di0/1_clk_root is base clock for display interface. The timebase

(fundamental) of Display clock (DISP_CLK) is configured by using

DI#_DISP_CLK_PERIOD, and then the waveform is created by using the settings

stored in DI#_DISP_CLK_OFFSET, DI#_DISP_CLK_UP and DI#_DISP_CLK_DOWN bit fields.

In addition to the Reference Manual clock scheme is described in the next app

note.

AN4140 : i.MX51 WinCE Clock Setting

< http://cache.freescale.com/files/dsp/doc/app_note/AN4140.pdf >

As we can see, it is possible to use different PLLs for different modules and

one can adapt clocking as needed, without affected other modules.

Have a great day,
Yuri

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i.MX ProcessorsのトピックIPUv3 How to change DISP_CLK waveform

IPUv3 How to change DISP_CLK waveform

Re: IPUv3 How to change DISP_CLK waveform