Specifications

S1C6P466 TECHNICAL MANUAL EPSON 25
CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Input Ports)
4.4 Input Ports (K00–K03 and K10–K13)
4.4.1 Configuration of input ports
The S1C6P466 has eight bits of general-purpose input ports. Each of the input port terminals (K00–K03,
K10–K13) provides a pull-up resistor.
Figure 4.4.1.1 shows the configuration of the input port.
Kxx
Address
V
DD
Interrupt
request
Data bus
VSS
Fig. 4.4.1.1 Configuration of input port
4.4.2 Interrupt function
All eight bits of the input ports (K00–K03, K10–K13) provide the interrupt function. The conditions for
issuing an interrupt can be set by the software. Further, whether to mask the interrupt function can be
selected by the software.
Figure 4.4.2.1 shows the configuration of K00–K03 (K10–K13) interrupt circuit.
Data bus
Input comparison
register (KCP00, 10)
K00, 10
Interrupt
request
Interrupt selection
register (SIK00, 10)
Address
Address
Address
Address
Interrupt factor
flag (IK0, 1)
K01, 11
K02, 12
K03, 13
Interrupt mask
register (EIK0, 1)
Address
Fig. 4.4.2.1 Input interrupt circuit configuration