Venkatraman Vaitheeswaran

iMX25 pixel clock

Discussion created by Venkatraman Vaitheeswaran on Apr 6, 2012
Latest reply on May 2, 2012 by Venkatraman Vaitheeswaran

Hello,

I am trying to use an optrex 3.5" LCD with the foll spec:

refresh rate: 50
x – resolution: 320
y –resolution: 240
pixel clock: 9.8MHz
left_margin: Horizontal back porch: 68
right_margin: Horizontal front porch: 20
upper_margin: Vertical back porch: 2
lower_margin: Vertical front porch: 2
hsync_len: HSYNC width: 30
vsync_len: VSYNC width: 11
sync; (VERTICAL / HORIZONTAL SYNC HIGH ACTIVE): VERTICAL / HORIZONTAL SYNC Active Low
vmode; (NON INTERLACED/ INTERLACED / ODD / DOUBLE): NON INTERLACED

The following changes were made to mxc_modedb.c:

"LCD_OPTREX", 50, 320, 240, 102040, 68, 20, 2, 2, 30, 11,
/*FB_SYNC_OE_LOW_ACT,*/
FB_SYNC_CLK_LAT_FALL,
FB_VMODE_NONINTERLACED,
0,},

where LCD_OPTREX would be the name i have assigned.


Everything works fine (display, apps show up, TS), except that I don't get the splash screen (kernel boot logo)!

The 102040 value was arrived at by doing a KHZ2PICO(9800) {9.8MHz pixel clock}. Is this wrong?

Observations:

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