A/D And I/O Circuits - UBI EasyCoder 501 Service Manual

UBI EasyCoder 501 – Service Manual
17. CPU BOARD, cont'd.
17.6:2

A/D and I/O Circuits

AD0-A15,A1-A20
ADREADY 26
WR
CSAD
+5V
RD
R13
AD–P24
R14
AD–LSS
R15
AD–VIN
AD–TEMP R16
R18
AD–RES
C5
GND
+5V
R27
R28
R30
R32
+5V
VCC
AD7 30
D7
AD6 31
D6
AD5 32
D5
AD4 33
D4
34
NC
AD3 35
D3
AD2 36
D2
AD1 37
D1
AD0 38
D0
RESET 39
RESET
+5V
1
RD
WR
CSRTC
/RESET
+5V
A1
A2
A3
A4
18 AD6
INTR DB6
27 17 AD7
WR DB7
28 GND
CS GND
ADC0848M
1 15
NC NC
14
VCC VREF
3 13 GND
IC21
RD AGND
4 12
CH1 CH8
C6 C8 C9
C7
+5V
R25
R29
1 RN5
R31
R33
2 3 4 5 6
GND
17
PC1
16
PC0
15
PC4
IC22
14
PC5
13
PC6
12
NC
11
PC7
8255AM 10 A1
A0
9 A2
A1
GND
GND
7 CS8255A
CS
IC20
8 18 VEE
RD VBB
10
WR
2
CS0
15 1
CS1 STDP
3
ALE
4 14 AD4
A0 D0
5 13 AD5
A1 D1
6 12 AD6
A2 D2
7 11 AD7
A3 D3
RTC-72421
+5V
+5V
1
C4
2 3
GND
+5V +5V
1 RN8 1
2 3 4 5 6 7 8 9 10 2
C12—C31
7 8 9 10
CGDATA
CGSTROB
CGLATCH
PPWREN
CGCLK
CGENABLE
CGSTART
OR–ON
+5V
VCC
30
AD7
D7
AD6 31
D6
IC23
AD5 32
D5
AD4 33
D4
34
NC
AD3 35
D3
AD2 36 8255AM
D2
37
AD1
D1
AD0 38
D0
RESET 39
RESET
+5V
1
RN9
4 5 6 7 8 9 10
RN7
3 4 5 6 7 8 9 10
+5V
+5V
C34—C39
GND
GND
VEE
C32—C33
+5V +5V
GND
17
PC1
16
PC0
15
PC4
14
PC5
13
PC6
12
NC
11 R23
PC7
10 A1
A0
9 A2
A1
GND
GND
7 CS8255B
CS
LIFT–HEAD
EN–ENG2
EN–ENG1
CUT–OUT
BEEPEN
EN-500
EN-DOUBLE
V24-EN
3 Q4
2
1
GND
121