EL640.480-A SB Series Operations Manual (020-0358-00A)
10
The EMC of the end product can be additionally improved using the four layer
board version of the display. One of the additional layers of this version is
dedicated to signal ground. It provides an efficient ground path for high
frequency interferences present in the system. See Ordering Information on
page 23.
For more details on improving the EMC of the end product please contact
Planar.
Display Operation Modes
The display supports all standard VGA display modes. It also supports the
NORMAL mode which is similar to that used by most other Planar products.
Mode selection is automatically performed by the display detecting the state
of _BLANK at rising edge of VS and the polarities of the VS and HS input signals
at the rising edge of the _BLANK signal. See timing diagrams on pages 12-14
for more details.
VGA Modes: In VGA modes _BLANK signal is used to frame the valid video
data. The number of active pixels in each VGA mode is determined by
calculating the number of VCLK pulses during the HS LOW time (T8 on timing
diagrams). The 320 column modes are detected additionally by the amount of
VCLK pulses during the front porch (T7 on VGA mode timing diagrams). In 320
and 360 column VGA modes each pixel data is displayed in two successive
pixels.
In 720 and 360 column VGA text modes the data of every ninth pixel is omitted
to be able to display the whole data line with 640 pixels. There is no data loss
due to blank data in the ninth column of the text box.
The border timing included in _BLANK is taken into account in the
interpretation of this signal and the video data during vertical borders is
displayed in 350 and 400 line modes but ignored in 480 line modes. See details
on setup and hold timing on page 15 and the timing of different VGA modes
on page 12-13.
Normal Mode: In this mode only seven input signals are needed: video data
(D0, D1, D2 and D3), video clock (VCLK), horizontal sync (HS) and vertical sync
(VS). _BLANK is not used and should be pulled HIGH or left disconnected.
In Normal Mode the last 640 pixels before the fall of the HS are displayed. The
topmost row displayed is the first HS HIGH time ending after HS Hold from VS
time (T3 in Normal Mode page 14) from the rising edge of the VS. See details
on setup and hold timing on page 15 and Normal Mode timing on page 14.
Timing Compatibility with Planar displays
The VGA mode detection of EL640.480-A SB series displays is compatible with
Planar EL640.480-AM series displays and EL7768MS display and is downwards
compatible with Planar EL640.400-C and -CB series displays (350 line and 400
line modes).
