Epson TM U200D - B/W Dot-matrix Printer Technical Manual page 60

CPU pin functions
Pin CPU
No. Function
9 P62
10 P63
11 P64
12 P65
13 P66
14 P67
15 VCC
16 P70
17 P71
18 P72/RXD1
19 P73/CLK1
20 P74/TXD1
21 RESET
22 CLK
23 VSS
24 X1
25 X2
26 EA
27 P75
28 P76
29 P77
30 P80
31 P81/INT0
32 P82
33 ALE
34 VCC
Rev. B
Signal Name I/O Level
NE I TTL
DK S I TTL
RE I TTL
HP DTC I TTL
DET I TTL
AC RST I TTL
VCC I (+5V)
CTS I TTL
CCE O TTL
RD I TTL
CLK IN/DTR I/O TTL
SD O TTL
RESET I ---
CLK O TTL
VSS I (0V)
X1 I ---
X2 O ---
EA I TTL
P75 (A16) O TTL
P76 (A17) O TTL
P77 (A18) O TTL
WDTOUT O TTL
CLK IN/DTR I TTL
PF SW I TTL
ALE O TTL
VCC I (+5V)
TM-U200D/U200PD Technical Manual
Description
Paper roll near-end detection Low: no paper
High: paper present
Drawer open/close Low: open
Paper roll end detection Low: paper present
High: no paper
Carriage Detector low: home position
Host interface DET
Auto cutter position detection (reset)
Main power terminal
Host interface CTS Low: on
4M ROM CE signal Low: active
Host interface RD Low:on
Host interface CLK IN/DTR
Host interface SD Low: on
CPU reset input Low: on
Not used. Open
GND terminal
Connected to ceramic vibration generator.
f=14.74MHz ± 0.5%
Connected to ceramic. f=14.74MHz ± 0.5%
External memory access Low: external ROM
High: internal ROM (CPU mask)
External memory address A16 (software)
External memory address A17 (software)
External memory address A18 (software)
Watch dog timer error (and hardware limited
time power supply switch) Low: error (reset)
Connected to pin #19
Paper feed switch Low: active
Address latch enable signal
Latch address on the bus AD0 to AD7 at falling.
Main power terminal (+5V)
Mechanism Configuration and Operating Principles