S1C63358 TECHNICAL MANUAL
EPSON
35
CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Input Ports)
4.5 Input Ports (K00–K03, K10–K13 and K20)
4.5.1 Configuration of input ports
The S1C63358 has nine bits general-purpose input ports. Each of the input port terminals (K00–K03, K10–
K13, K20) provides internal pull-up resistor. Pull-up resistor can be selected for each bit with the mask
option.
Figure 4.5.1.1 shows the configuration of input port (K00–K03, K10–K13).
Figure 4.5.1.2 shows the configuration of input port (K20).
Kxx
Mask option
Address
V
DD
Interrupt
request
Data bus
V
SS
Fig. 4.5.1.1 Configuration of input port (K00–K03, K10–K13)
K20
Mask option
V
DD
Interrupt
request
Data bus
V
SS
Key sense
ON/OFF control
Address
Address
Fig. 4.5.1.2 Configuration of input port (K20)
Selection of "With pull-up resistor" with the mask option suits input from the push switch, key matrix,
and so forth. When "Gate direct" is selected, the port can be used for slide switch input and interfacing
with other LSIs.
