Eurotech Appliances PXA270 Computer Hardware User Manual


 
ZEUS Technical Manual Detailed hardware description
© 2007 Eurotech Ltd Issue D 44
Flat panel display
The PXA270 processor contains an integrated LCD display controller. It is capable of
supporting both colour and monochrome single- and dual-scan display modules. It
supports active (TFT) and passive (STN) LCD displays up to 800x600 pixels.
The PXA270 can drive displays with a resolution up to 800x600, but as the PXA270
has a unified memory structure, the bandwidth to the application decreases
significantly. If the application makes significant use of memory, such as when video is
on screen, you may also experience FIFO under-runs causing the frame rates to drop
or display image disruption. Reducing the frame rate to the slowest speed possible
gives the maximum bandwidth to the application. The display quality for an 800x600
resolution LCD is dependant on the compromises that can be made between the LCD
refresh rate and the application. The PXA270 is optimized for a 640x480 display
resolution.
A full explanation of the graphics controller operation can be found in the Intel PXA27x
Processor Family Developer’s Manual included on the Development Kit CD.
The ZEUS-FPIF
interface board allows the user to easily wire-up a panel using pin and
crimp style connectors (see page 122
). Contact Eurotech Sales (see page 97) for
purchasing information. Alternatively, the display interface is connected to an LVDS
interface (see the section LVDS interface
, page 47). This may be useful when driving
displays located more than 300mm (12") from the ZEUS.
The following tables provide a cross-reference between the flat panel data signals and
their function when configured for different displays.
TFT panel data bit mapping to the ZEUS
The PXA270 can directly interface to 18-bit displays, but from a performance
point of view it is better to use 16-bit only. 18-bit operation requires twice the
bandwidth of 16-bit operation.
The following table shows TFT panel data bit mapping to the ZEUS:
Panel data bus bit 18-bit TFT 12-bit TFT 9-bit TFT
FPD 15 R5 R3 R2
FPD 14 R4 R2 R1
FPD 13 R3 R1 R0
FPD 12 R2 R0 -
FPD 11 R1 - -
GND R0 - -
FPD 10 G5 G3 G2
FPD 9 G4 G2 G1
FPD 8 G3 G1 G0
continued…