upd4701a Renesas Electronics Corporation., upd4701a Datasheet - Page 6

• Manufacturer Part Number: upd4701a
• Description: Mos Integrated Circuit
• Manufacturer: Renesas Electronics Corporation.

6. CONNECTION TO CPU SYSTEM
6
The application circuits and their parameters are for reference only and are not intended for use in actual design-ins.
An example of connection to a CPU system is shown in Fig. 4.
The above connections enable the CPU to read the X counter, Y counter and switch input status.
PD4701A Pin Name
X/Y
U/L
CS
D
SF, CF
RESET X
RESET Y
0 to 7
CPU System
A
2
- A
Connected to address line A
Connected to address line A
Connects address lines A
address mode or MRD in the memory address mode, or an output port. The low level must be
maintained during a count data read.
Connected to the data bus.
When these are used as interrupt signals, they are connected to the CPU INT pin.
These are connected to a CPU output port or reset signal.
n
Output Port
and IORD
or MRD
Fig. 4 Example of Connection to CPU System
DB
INT
0 - 7
A
A
1
0
FLAG
2
to A
1
0
.
.
n
and the signal resulting from decoding IORD in the I/O
Description
CS
X/Y
U/L
D
SF
CF
Mouse I/F
RESET
0 - 7
PD4701A
X Y
MIDDLE
RIGHT
LEFT
X
X
Y
Y
A
B
A
B
Mouse
PD4701A