UPD4701AGT NEC [NEC], UPD4701AGT Datasheet - Page 5

• Manufacturer Part Number: UPD4701AGT
• Description: MOS INTEGRATED CIRCUIT
• Manufacturer: NEC [NEC]

3. SWITCH INPUT OPERATION
of the count data upper byte together with the switch flag status as an internal status (see Fig. 3). These are all active-
“H” outputs. The switch flag status, SF, is equivalent to the switch flag output, SF, described below.
4. OPERATION OF SWITCH FLAG, SF
5. DATA READ OPERATION
is shown in Table 1. (At this time, the data latched on the falling edge of CS is output. If X/Y or U/L is switched while
CS is still “L”, the data at the point at which CS changes from “H” to “L” is read. When CS is set to “H”, new data is
read into the latch, and the new data is confirmed on the next fall of CS.
The PD4701A can process up to 3 contact points as switch inputs (active-“L” input). Switch input is read as part
The switch flag, SF, becomes active (active-“L” output) when the RIGHT, LEFT or MIDDLE switch input is “L”.
SF can also be read as the switch flag status together with the count data.
The CPU reads the count data and switch input status by controlling CS, X/Y and U/L. The relation between these
CS
0
0
0
0
1
Upper Byte
Lower Byte
X/Y
0
0
1
1
Bit No.
Bit No.
U/L
0
1
0
1
Table 1 Data Output Table
Fig. 3 Data Output Format
X
Y
SF
SF
D
C
C
7
SF
C
7
7
7
7
7
C
X
Y
11 - 0
D
SF : Switch Flag
C
C
L
L
C
R : Right Switch
M : Middle Switch
6
L
6
6
L : Left Switch
6
6
6
: Count Data (12 bit )
X
Y
C
D
R
R
R
5
5
C
C
5
5
5
5
FLOATING
C
M
X
Y
4
4
D
M
M
C
C
4
4
4
4
C
C
3
3
11
X
Y
X
Y
3
D
C
C
C
C
3
11
11
3
3
C
C
2
2
10
2
X
Y
X
Y
D
C
C
C
C
2
10
10
2
2
C
C
1
1
9
1
X
X
Y
Y
D
C
C
C
C
C
C
0
0
1
1
9
1
9
8
0
X
X
Y
Y
D
C
C
C
C
0
0
8
0
8
PD4701A
5