CCU 3000, CCU 3000-I
CCU 3001, CCU 3001-I
Mode 1
bit 5,4,3,2,1,0
Switch I/O –
port select mode
0... I/O line (default)
1... port select
direction switch
for I/O lines 5 ... 0
1... input (default)
0... output
Data 3
bit 5
bit 4
bit 3
bit 2
bit 1
bit 0
I/O 5 or RDPort 1
I/O 4 or WRPort 1
I/O 3 or RDPort 2
I/O 2 or WRPort 2
I/O 1 or RDPort 3
I/O 0 or WRPort 3
Direction 2
bit 5,4,3,2,1,0
D0...D7
Data valid
WR Port 1...3
RD Port 1...3
Fig. 2–1:
Timing diagram
D0...D7
CCU 3000,
CCU 3001
Port 1
in
P55
P54
P53
P52
Port 1
out
Port 2
in
e.g. ‘244
e.g. ‘374
D0...D7
Memory
OE
Port 2
out
Port 3
in
Port 3
out
P51
P50
P76
R/W
Fig. 2–2:
External reproduction of ports 1 to 3
2.8. Special Mode of Port 7
Each line of port 7 can be switched independently into
a special mode. This mode is selected by the mode con-
trol register. After reset this register is set to 0 (= Port
mode). A “1” in this register turns this line into the special
mode. As the control signals are all outputs, the direction
for those lines must be defined as outputs (reset condi-
tion = inputs)
6
Special Mode of
P77
P76
P75 ...P70
Function
Power-down control for ext.
memory
R/W output
6 bit banking addresses with
common home bank logic
All special mode signals have push-pull outputs. (Port
mode: open drain).
MICRONAS INTERMETALL
MICRONAS [ MICRONAS ]
