2008-05-21 21:34:47     Can PPI attch the VGA TFT-LCD use internal timer?

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2008-05-21 21:34:47     Can PPI attch the VGA TFT-LCD use internal timer?

Wei Jiang (CHINA)

Message: 56111   

 

Dear all,

 

    My hardware is BF561, kernel: 08R1-RC8. CCLK:600M, SCLK:120M

 

    I attached a VGA(640*480) TFT-LCD to the PPI1. And timer10 and timer11 is used for PPI_SYNC1 and PPI_SYNC2. My problem is:

 

    when the PPICLK is bigger than 12M, then the waveform from two timers is astable. I means the  phase difference is not stationary even I used the timer-source from SCLK or PPI_CLK.

 

    I thought the driver is simple and I checked it again and again. So I'm wondering whether the PPI can do this.. Did anyone do the same work before?

 

    Please advice, any clue would be greatly appreciated. thanks.

 

                Wei Jiang

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2008-05-22 10:37:05     Re: Can PPI attch the VGA TFT-LCD use internal timer?

Robin Getz (UNITED STATES)

Message: 56149   

 

Wei:

 

If you need frame syncs, then use the PPI frame syncs. Did you configure things as frame syncs or timers?

 

for PPI1:

PPI1SYNC1/TMR10

PPI1SYNC2/TMR11

PPI1SYNC3

 

 

-Robin

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2008-05-22 21:48:03     Re: Can PPI attch the VGA TFT-LCD use internal timer?

Wei Jiang (CHINA)

Message: 56163   

 

Dear Robin:

 

    I think I configured the registers as frame syncs.

 

   #define PPI_CONFIG_VALUE                (PORT_DIR|XFR_TYPE|DMA32|POLC|DLEN(16)|0x10)

 

   #define TIMER_CONFIG                    (PWM_OUT|PERIOD_CNT|TIN_SEL|CLK_SEL|PULSE_HI)

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