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4 i/o memory of input ports, And "0" when the voltage goes low (v – Epson S1C63558 User Manual

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EPSON

S1C63558 TECHNICAL MANUAL

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Input Ports)

4.4.4 I/O memory of input ports

Table 4.4.4.1 shows the I/O addresses and the control bits for the input ports.

Table 4.4.4.1 Control bits of input ports

Address

Comment

D3

D2

Register

D1

D0

Name

Init

1

1

0

FF20H

SIK03

SIK02

SIK01

SIK00

R/W

SIK03

SIK02

SIK01

SIK00

0

0

0

0

Enable

Enable

Enable

Enable

Disable

Disable

Disable

Disable

K00–K03 interrupt selection register

FF21H

K03

K02

K01

K00

R

K03

K02

K01

K00

2

2

2

2

High

High

High

High

Low

Low

Low

Low

K00–K03 input port data

FF22H

KCP03

KCP02

KCP01

KCP00

R/W

KCP03

KCP02

KCP01

KCP00

1

1

1

1

K00–K03 input comparison register

FF24H

SIK13

SIK12

SIK11

SIK10

R/W

SIK13

SIK12

SIK11

SIK10

0

0

0

0

Enable

Enable

Enable

Enable

Disable

Disable

Disable

Disable

K10–K13 interrupt selection register

FF25H

K13

K12

K11

K10

R

K13

K12

K11

K10

2

2

2

2

High

High

High

High

Low

Low

Low

Low

K10–K13 input port data

FF26H

KCP13

KCP12

KCP11

KCP10

R/W

KCP13

KCP12

KCP11

KCP10

1

1

1

1

K10–K13 input comparison register

FFE4H

0

0

0

EIK0

R

R/W

0

3

0

3

0

3

EIK0

2

2

2

0

Enable

Mask

Unused

Unused

Unused

Interrupt mask register (K00–K03)

FFE5H

0

0

0

EIK1

R

R/W

0

3

0

3

0

3

EIK1

2

2

2

0

Enable

Mask

Unused

Unused

Unused

Interrupt mask register (K10–K13)

FFF4H

0

0

0

IK0

R

R/W

0

3

0

3

0

3

IK0

2

2

2

0

(R)

Yes

(W)

Reset

(R)

No

(W)

Invalid

Unused

Unused

Unused

Interrupt factor flag (K00–K03)

FFF5H

0

0

0

IK1

R

R/W

0

3

0

3

0

3

IK1

2

2

2

0

(R)

Yes

(W)

Reset

(R)

No

(W)

Invalid

Unused

Unused

Unused

Interrupt factor flag (K10–K13)

*1 Initial value at initial reset

*2 Not set in the circuit

*3 Constantly "0" when being read

K00–K03: K0 port input port data (FF21H)
K10–K13: K1 port input port data (FF25H)

Input data of the input port terminals can be read with these registers.

When "1" is read: High level
When "0" is read: Low level

Writing: Invalid

The reading is "1" when the terminal voltage of the eight bits of the input ports (K00–K03, K10–K13) goes
high (V

DD

), and "0" when the voltage goes low (V

SS

).

These bits are dedicated for reading, so writing cannot be done.