Daewoo DVDP485, Руководство по обслуживанию

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CT908
PRELIMINARY, SUBJECT TO CHANGE WITHOUT NOTICE CTK CONFIDENTIAL, NO DISCLOSURE
The above information is the exclusive intellectual property of Cheertek Inc. and shall not be disclosed, distributed or reproduced without permission from Cheertek Inc.
Copyright (C) 2003 Cheertek Inc. All Rights Reserved.
PORT3
[7:0]
I/O Port3 is an 8-bit bi-directional I/O port with internal
pull-up.
Port3 also serve following special functions:
P3.0 RXD1 (serial input port)
P3.1 TXD1 (serial output port)
P3.2 IR input connecting to IR receiver
P3.3: GPA6, general purpose IO bus A bit 6, initial in
input state
P3.4 T0 (timer 0 external input)
P3.5 T1 (timer 1 external input)
P3.6 WR# (external data memory write)
P3.7 RD# (external data memory read)
P3.3: INTM#, output
P3.6: WR#, input
P3.7: RD#, input
PORT4
[7:0]
I/O Port4 is an 8-bit bi-directional I/O port with internal
pull-up. It can be used for bank selection of external
program and data memories, internally latched with
ALE.
PORT5
[7:0]
I/O Port5 is an 8-bit bi-directional I/O port , default in
input state.
FWR# O Flash write enable output
4.2.1
External Micro-controller Mode
Pin name Type Description
ALE I Address latch enable. It is used to latch the low byte address of SAD[7:0] as
LATS=0.
LATS I Low byte address conveying type select, input only.
LATS=0, mux with SAD[7:0];
LATS=1, conveyed on SA[7:0].
SAD[7:0] I/O When ALE is active (ALE=1), it is the low byte of the address. And it is
time-multiplexed with the data byte being written(WR# active) or
read(RD# active).