
S1C88409 TECHNICAL MANUAL
EPSON
69
CHAPTER 5: PERIPHERAL CIRCUITS AND OPERATION (Input Ports)
5.6.3 Interrupt function
All the input ports provide the interrupt function.
The input ports are divided into five systems: K0
(K00–K07), K10, K11, K12 and K13. The interrupt
generation condition for each system can be set
with software.
When the interrupt generation condition set for
each terminal system is met, the interrupt factor
flag (FK0, FK10, FK11, FK12 and FK13) corre-
sponding to the terminal system is set to "1", and
an interrupt is generated.
The interrupt can be prohibited by setting the
interrupt enable register (EK0, EK10, EK11, EK12
and EK13) corresponding to each interrupt factor
flag.
Furthermore, the priority level of the input
interrupt for the CPU can be set at an optional
level (0–3) using the interrupt priority registers
PK0 and PK1 (two bits each) corresponding to two
systems K0 and K1.
Refer to Section 5.20, "Interrupt and Standby
Mode", for details of the interrupt control registers
and operations subsequent to interrupt generation.
The exception processing vectors for each inter-
rupt factor are set as follows:
K10 input interrupt: 000006H
K11 input interrupt: 000008H
K12 input interrupt: 00000AH
K13 input interrupt: 00000CH
K0 input interrupt: 00000EH
K0 input interrupt
Figure 5.6.3.1 shows the configuration of the K0
(K00–K07) input interrupt circuit.
Data
bus
K07
K06
K05
K04
K03
K02
K00
Input comparison
register KCP00
Interrupt selection
register SIK00
Address
K01
Input port
K00D
Interrupt priority
level judgment
circuit
Interrupt
priority
register
PK00, PK01
Interrupt
request
IRK0
Interrupt factor flag
FK0
Address
Interrupt enable
register EK0
Address
Fig. 5.6.3.1 Configuration of K0 input interrupt circuit