Draft 1/16/97
3-6
Signal Denitions
PRE.4 for Rev. D
Copyright 1997 by LSI Logic Corporation. All rights reserved.
AVERR
Audio Video Error
Output
This active LOW output signal indicates that the data
coming out on AVSD or AUXD[7:0] contains an error.
This signal should be latched on the LOW-to-HIGH tran-
sition of the AVCLK signal in serial mode. AVERR is a
valid indicator if it is latched when the VVALID or AVALID
signal is asserted. The signal can be used to invoke error
handling in the L64002 Video/Audio decoder.
AVSD
Audio Video Serial Data
Output
This active HIGH output signal transfers serial video and
audio data to external A/V decoder devices, such as the
L64002. Data is stable on this line on the LOW-to-HIGH
transition of AVCLK signal and when VVALID or AVALID
are active HIGH.
VREQ
Video Data Request
Input
This active LOW input signal indicates that the external
video decoder requests video data.
VVALID
Video Data Valid
Output
This active HIGH output signal indicates that valid video
data is being output to the L64002. In serial mode, when
VVALID is asserted, video data coming on AVSD is
latched in the L64002 on the rising edge of AVCLK. In
parallel mode, the rising edge of VVALID latches video
data on the AUX[7:0] in the L64002.
3.4
Pass-Through
L64002 Host
Processor
Interface
AV_CS
L64002 Chip Select
Output
This active LOW output signal allows the host processor
connected to the L64007 to directly control the operation
of the L64002. This signal is asserted when the external
host processor accesses the address mapped locations
devoted to L64002 access. AUX_DATA[7:0] are used as
data lines connecting the L64007 and the L64002. The
read or write direction is determined by the R/W signal.
AV_WAIT
L64002 Wait
Input
This active LOW input signal is used by the L64002 to
prevent the L64007 from completing a host processor
read or write cycle to the L64002. The L64007 does not
assert DTACK until AV_WAIT is deasserted and indicates
that the bus cycle can be completed. When the L64007