Printer User Manual

Table A-3. CN4 Pin Assignments (Continued)
Pin No. Signal Name I/O Description
21
RD
O
Read strobe signal
22
WR
O
Write strobe signal
23
IREQ
O
Interrupt to option
24
NMI
O
Non-maskable interrupt
25
DREQ
O
Data request
26
DTCT
I
LT option used/unused
27
VCC
—
+5 VDC
28
VCC
—
+5 VDC
29
VCC
—
+5 VDC
30
VCC
—
+5 VDC
31
TXD+
—
Not used
32
TXD-
—
Not used
33
RXD+
—
Not used
34
RXD-
—
Not used
35
DTR
—
Not used
36
CTS
—
Not used
37
NC
—
Not used
38
NC
—
Not used
39
LCD
—
Not used
40
SWRD
—
Not used
41
GND
—
Ground
42
GND
—
Ground
43
GND
—
Ground
44
GND
—
Ground
45
RESET
O
Reset signal
46
INH
O
I/F disabled
47
CMREQ
I
Request command
48
WRRDY
I
I/F ready
49
RDREQ
I
Data read request
50
WRT
O
Write enable
51
RDT
O
Read enable
52
TYPB
I
Type-B I/F used/unused
53
TXD
—
Not used
54
READY
—
Not used
55
RXD
—
Not used
56
NC
—
Not connected
57
VCC
—
+5 VDC
58
VCC
—
+5 VDC
59
VCC
—
+5 VDC
60
VCC
—
+5 VDC
Appendix EPL-5500 Service Manual
A-6 Rev. A