V
IDBLOX
3G-SL
AND
3G-NE
RX
M
ODULE
Publication 81-9059-0667-0, Rev. C
March 2011
Proprietary Information of PESA
4-25
Modelines
Device resolution may be presented in the form of a Modeline, which is a character string of a specific
syntax that contains the pixel count, frequency and sync timing parameters for the specific resolution.
Modelines for specific devices are sometimes used to convey resolution data rather than a table or chart;
and there are software applications that, when connected to a specific device, can generate a modeline
for that device.
Whether you obtain a modeline for your device through a software generator or from a reference source,
it contains at least ten parameters beginning with a label for the resolution being specified, followed by
a second parameter that specifies pixel clock rate in MHz. Next there are four numbers that specify the
horizontal resolution and sync timing parameters, followed by four numbers that specify the vertical
resolution and sync timing. These parameters may be followed by one or more optional flag entries that
specify sync polarity and other characteristics. Modeline data is always presented in the following
syntax:
“Label” Pclk Hdisp Hsyncstart Hsyncend Htotal Vdisp Vsyncstart Vsyncend Vtotal [flags]
Flags (optional): +HSync, -HSync, +VSync, -VSync, Interlace, DoubleScan, CSync, +CSync, -CSync
Here’s an example modeline for a device with a resolution of 1600X1200 @ 59.92Hz
Modeline "1600x1200" 155 1600 1656 1776 2048 1200 1202 1205 1263
Each entry for the modeline is introduced and discussed in Table 4-1.
Modeline information presented in the following example and in Table 4-1
is for informational purposes only. The numbers used in these examples
may not apply to your specific requirements.
In some reference sources, you may see the modeline split into multiple lines for greater clarity as
shown here:
Modeline "1600x1200" 155 1600 1656 1776 2048
1200 1202 1205 1263
Using modeline parameters, horizontal and vertical frequencies can be calculated by:
Hfreq = Pclk / Htotal
Vfreq = Pclk / (Htotal X Vtotal) (field rate)
For interlace mode, frame rate = field rate/2, otherwise frame rate = field rate.
Summary of Contents for VIDBLOX 3G-NE RX
Page 57: ......