Philips Semiconductors
Preliminary specification
PAL/NTSC/SECAM video decoder with adaptive PAL/NTSC
comb filter, VBI-data slicer and high performance scaler
SAA7114H
9.4
Video expansion port (X-port)
As output, these are direct copies of the decoder signals.
The expansion port is intended for transporting video
streams image data from other digital video circuits like
MPEG encoder/decoder and video phone codec, to the
image port (I-port).
The data transfers through the expansion port represent a
single D1 port, with half duplex mode. The SAV and EAV
codes may be inserted optionally for data input (controlled
by bit XCODE[92H[3]]). The input/output direction is
switched for complete fields, only.
The expansion port consists of two groups of signals/pins:
• 8-bit data, I/O, regularly components video
YUV 4 : 2 : 2, i.e. CB-Y-CR-Y, byte serial, exceptionally
raw video samples (e.g. ADC test). In input mode the
data bus can be extended to 16-bit by the pins
HPD7 to HPD0.
• Clock, synchronization and auxiliary signals,
accompanying the data stream, I/O.
Table 26 Signals dedicated to the expansion port
SYMBOL
PIN
I/O
DESCRIPTION
BIT
XPD7 to
XPD0
81, 82, I/O X-port data: in output mode controlled by decoder
OFTS[2:0]13H[2:0];
91H[7:0] and C1H[7:0]
84 to 87,
section, data format see Table 27; in input mode
YUV 4 : 2 : 2 serial input data or luminance part of
a 16-bit YUV 4 : 2 : 2 input
89 and 90
XCLK
94
I/O clock at expansion port: if output, then copy of LLC; XCKS[92H[0]]
as input normally a double pixel clock of up to
32 MHz or a gated clock (clock gated with a
qualifier)
XDQ
95
96
I/O data valid flag of the expansion port input (qualifier):
if output, then decoder (HREF and VGATE) gate
(see Fig.23)
−
XRDY
O
data request flag = ready to receive, to work with
optional buffer in external device, to prevent internal
buffer overflow;
XRQT[83H[2]]
second function: input related task flag A/B
XRH
XRV
XTRI
92
91
80
I/O horizontal reference signal for the X-port: as output: XRHS[13H[6]], XFDH[92H[6]] and
HREF or HS from the decoder (see Fig.23); as
input: a reference edge for horizontal input timing
and a polarity for input field ID detection can be
defined
XDH[92H[2]]
I/O vertical reference signal for the X-port: as output:
V123 or field ID from the decoder,
XRVS[1:0]13H[5:4], XFDV[92H[7]]
and XDV[1:0]92H[5:4]
see Figs 21 and 22; as input: a reference edge for
vertical input timing and for input field ID detection
can be defined
I
port control: switches X-port input 3-state
XPE[1:0]83H[1:0]
2000 Mar 15
62
NXP [ NXP ]
