Epson S1C6S3N2, Техническое руководство

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I-36
EPSON
S1C6S3N2 TECHNICAL HARDWARE
CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Input Ports)
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 five bits
of the input ports (K00–K03, K10) goes high (V
DD
), and "0"
when the voltage goes low (V
SS
).
These bits are dedicated for read-out, so writing cannot be
done.
Interrupt conditions can be set with these registers.
When read out is "1" : Falling edge
When read out is "0" : Rising edge
Read-out : Valid
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 differential registers (DFK00–DFK03 and
DFK10).
At initial reset, these registers are set to "0".
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 five bits.
At initial reset, these registers are all set to "0".
K00–K03, K10:
Input port data
(073H, 077H·D0)
DFK00–DFK03, DFK10:
Differential registers
(074H, 077H·D1)
EIK00–EIK03, EIK10:
Interrupt mask registers
(075H, 077H·D2)