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Table A-2. HD64180 Terminal Functions
Pin No.
Terminal
Description
Notes
3 2
I
+5 VDC
1, 33
Vss
—
GND
2
XTAL
I
External oscillator (1 2.2 MHz)
3
EXTAL
I
6 4
o
Pulled up
7
RESET
I
Reset
signal
(1 4A: ROUT, pin 21)
1 3 - 3 1
A O - A 1 8
0
Address bus (1 9-bit, 5 12K-byte)
3 4 - 4 1
Data bus (8-bit)
6 3
o
Read pulse
6 2
o
Write pulse
5 9
ME
o
Memory enable
(1 4A:
ME,
pin
4 5 )
58
o
Pulled up
4
WAIT
I
Pulled up
6 0
E
o
Enable (synchronous clock)
(1 4A: E, pin 53)
6
Pulled up
5
o
Pulled up
58
HALT
o
Pulled up
61
LIR
o
Pulled up
12
ST
o
Pulled up
57
o
Refresh signal
(1 4A:
pin 1 1)
8
NMI
I
Pulled down
9
INTO
I
Pulled up
10
I
Pulled
up
11
I
Interrupt 2
(1 B:
pin 37)
47
Data request signal
(2A: RDY, pin 32)
54
DREQ 1
Pulled up
55
TEND 1
0
Pulled up
45
TXAO
o
Pulled up
46
RXAO
I
Pulled up
4 2
RTSO
o
SCI channel O RTS
–
IC
PB2, pin 1 1)
43
CTSO
I
SCI channel O CTS
PB3, pin 12)
44
DCDO ,
I
Pulled down
—
48
TXA
i
External serial l/F
49
RXA 1
External serial
RXD
50
CKA 1
‘ Pulled up
51
TXS
o
CSO
TXD
RXD, pin 18)
52
RXS
I
CSO l/O RXD
p i n 1 7 )
53
CKS
CS
clock
SCK,
pin 19)
A-4
Summary of Contents for LQ-2550
Page 1: ...L Q 2 5 5 0 TECHNICAL MANUAL EPSON ...
Page 240: ...REV A P r cl Figure 6 3 LQ 2550 Lubrication and Adhesive Application Points Diagram 2 6 3 ...
Page 241: ...REV A 7 i_ Figure 6 4 LQ 2550 Lubrication and Adhesive Application Points Diagram 3 6 4 ...
Page 252: ...REV A I 1 I 7 v m o m x b Figure A 6 PPD781OHG Block Diagram A 7 ...
Page 297: ...REV A 1 L I Irl N I i t 1 I I x Figure A 50 ROPSE Board Circuit Diagram A 52 ...