
S1C60N08 TECHNICAL HARDWARE
EPSON
I-25
CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Input Ports)
K00–K03, K10, K20–K23: Input port data (2E3H, 2E7HD0, 2F4H)
Input data of the input port terminals can be read out with these registers.
When "1" is read out : High level
When "0" is read out : Low level
Writing : Invalid
The read-out is "1" when the terminal voltage of the nine bits of the input ports (K00–K03, K10, K20–K23)
goes high (VDD), and "0" when the voltage goes low (VSS).
These bits are dedicated for read-out, so writing cannot be done.
KCP00–KCP03, KCP10: Input comparison registers (2E4H, 2E7HD1)
Interrupt conditions for terminals K00–K03 and K10 can be set with these registers.
When "1" is written : Falling edge
When "0" is written : Rising edge
Read-out : Valid
Of the nine bits of the input ports, the interrupt conditions can be set for the rising or falling edge of
input for each of the five bits (K00–K03 and K10), through the input comparison registers (KCP00–KCP03
and KCP10).
At initial reset, these registers are set to "0".
EIK00–EIK03, EIK10, EIK20–EIK23: Interrupt mask registers (2E5H, 2E7HD2, 2F5H)
Masking the interrupt of the input port terminals can be selected with these registers.
When "1" is written : Enable
When "0" is written : Mask
Read-out : Valid
With these registers, masking of the input port bits can be selected for each of the nine bits.
Writing to the interrupt mask registers can be done only in the DI status (interrupt flag = "0").
At initial reset, these registers are all set to "0".
IK0, IK1, IK2: Interrupt factor flags (2EAHD2 and D3, 2F3HD1)
These flags indicate the occurrence of input interrupt.
When "1" is read out : Interrupt has occurred
When "0" is read out : Interrupt has not occurred
Writing : Invalid
The interrupt factor flags IK0, IK1 and IK2 are associated with K00–K03, K10 and K20–K23, respectively.
From the status of these flags, the software can decide whether an input interrupt has occurred.
These flags are reset when the software reads them. Read-out can be done only in the DI status (interrupt
flag = "0").
At initial reset, these flags are set to "0".