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CHAPTER 12 PORT FUNCTIONS
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User’s Manual U15195EJ5V0UD
12.3.8 Port CT
Port CT is a 4-bit I/O port in which input or output can be specified in 1-bit units.
7
−
PCT
6
PCT6
5
−
4
PCT4
3
−
2
−
1
PCT1
0
PCT0
Address
FFFFF00AH
After reset
Undefined
Bit position
Bit name
Function
6, 4, 1, 0
PCTn
(n = 6, 4, 1, 0)
I/O port
Besides functioning as a port, in control mode, this can operate as control signal outputs when memory is
expanded externally.
(1) Operation in control mode
Port
Alternate Pin Name
Remarks
Block Type
PCT0 LWR
PCT1 UWR
Write strobe signal output
PCT4
RD
Read strobe signal output
Port CT
PCT6
ASTB
Address strobe signal output
I