Sharp ER-A450T - Page 22

2) Block diagram
3) Pin description
Pin
NO.
Name ER-A770 I/O Description
1 SL00 VCC ISU RS-232/UNIT0
channel select
2 SL01 GND ISU
3 SL02 GND ISU
4 SL10 GND ISU RS-232/UNIT1
channel select
5 SL11 GND ISU
6 SL12 GND ISU
7 SL20 GND ISU RS-232/UNIT2
channel select
8 SL21 GND ISU
9 SL22 GND ISU
10 SL30 GND ISU RS-232/UNIT3
channel select
11 SL31 GND ISU
12 SL32 GND ISU
13 /CD0 /DCD1 IS
RS-232 control
signal /CD input
14 BRK0 BRK1 IS RS-232 break signal
15 TRNEMP0 TRENMP1 IS
RS-232 transmission
buffer empty signal
16 RCVRDY0 RCVRDY1 IS
RS-232 data reception
enable signal
17 TRNRDY0 TRNRDY1 IS
RS-232 transmission
enable signal
18 /CTS0 /CTS1 IS
RS-232 clear to
send signal
19 RCVDT0 RCVDT1 IS
RS-232 reception
data signal
20 VCC VCC +5V
21 GND GND GND
22 /CI0 /CI1 IS
RS-232 control
signal /CI input
23 /RTS0 /RTS1 O
RS-232 request to
send signal
24 /CS0 /CS1 O
RS-232 chip select
signal
25 /CD1 /DCD2 IS
RS-232 control
signal /CD input
Pin
NO.
Name ER-A770 I/O Description
26 BRK1 BRK2 IS GND
27 TRNEMP1 TRENMP2 IS GND
28 RCVRDY1 RCVRDY2 IS GND
29 TRNRDY1 TRNRDY2 IS GND
30 /CTS1 /CTS2 IS +5V
31 RCVDT1 RCVDT2 IS
RS-232 reception
data signal
32 /CI1 /CI2 IS
RS-232 control
signal /CI input
33 /RTS1 /RTS2 O
RS-232 request to
send signal
34 /CS1 /CS2 O
RS-232 chip select
signal
35 /CD2 VCC IS +5V
36 TRNEMP2 TRENMP3 IS GND
37 RCVRDY2 RCVRDY3 IS GND
38 TRNRDY2 TRNRDY3 IS GND
39 CTS2Z /CTS3 IS +5V
40 RCVDT2 RCVDT3 IS GND
41 /CI2 VCC IS +5V
42 /CS2 /CS3 O NU
43 /CD3 /SINT IS
RS-232: /CD,
IN-LINE : /P1
44 BRK3 GND IS GND
45 TRNEMP3 GND IS GND
46 RCVRDY3 GND IS GND
47 TRNRDY3 GND IS GND
48 /CTS3 GND IS GND
49 RCVDT3 GND IS GND
50 /CI3 GND IS GND
51 /CS3 /SRCS O
RS-232/INLINE chip
select signal
52 D0 D0 IO Data bus (CPU)
53 D1 D1 IO Data bus (CPU)
USART
A
USART
B
USART
C
USART
D
USART
OPC1
DATA BUS
OPC1~USART
OPC2
Common input
BAUD RATE GENERATOR BAUD RATE GENERATOR
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