PXD20RM Datasheet, PDF (455/1628 Pages) Freescale Semiconductor, Inc – PXD20 Microcontroller

pdi_clk
Table 11-79. XYh Value (continued)
Bit
Value
Description
3
P3 Protection bits (used to detect ECC
2
P2 errors). It would not be used for bit
1
P1 correction.
0
P0
16-bit RGB (narrow mode) with internal sync (Representation –
pdi_data [7:0]
FF 00 00 XY
Note: Preamble sequence is independent of data sequence
Figure 11-96. Location of Sync Preamble in Narrow Mode
Sync Preamble would come continuously for 4 clock cycles as shown in Figure 11-96. It does not depend
upon which byte is coming first in data (MSB or LSB). Sync extraction is done using PDI[7:0] to identify
the horizontal and vertical blanking period using H and V field of the 'XYh' data as mentioned in
Table 11-79.
ITU 656 Sync preamble pattern (FFh 00h 00h) has to be masked out in the RGB and YCbCr data. The data
stream must not include FFh 00h 00h as the valid pixel data to avoid malfunction by the validation state
machine.
Horizontal blanking period must continue during the Vertical blanking period. The gap between 2
horizontal blanking periods should be the same during vertical blanking period as during line active. All
Vertical and horizontal parameter values are validated against the DCU3 registers programmed by the user.
Polarity of HSYNC and VSYNC are selectable. Horizontal blanking and vertical blanking must be aligned
as shown in Figure 11-97. During blanking period the input stream must be a 80h 10h 80h 10h sequence.
This sequence must be present during both horizontal (line) blanking and vertical (frame) blanking.
As the PDI does not support interlaced video, the Framing Bit (F field in XYh) will be ignored during
timing extraction. Narrow mode is compatible with RGB565 and YCbCr422 muxed modes. Each header
contains an ECC value, which the PDI will check. The PDI is capable of detecting an error but not
correcting it.
As with External sync mode, the value of front and back porch can be zero but the pulse width and TFT
screen parameter cannot be zero.
Freescale Semiconductor
PXD20 Microcontroller Reference Manual, Rev. 1
Preliminary—Subject to Change Without Notice
11-121