Freescale Semiconductor MCF51QE128RM manual Keyboard Interrupt 1 KBI1 Registers, KBI1 Pin Mapping

Models: MCF51QE128RM

1 424
Download 424 pages 63.71 Kb
Page 140
Image 140

Chapter 6 Parallel Input/Output Control

 

 

Table 6-51. PTJDS Register Field Descriptions

 

 

 

Field

 

Description

 

 

7–0

Output Drive Strength Selection for Port J Bits. Each of these control bits selects between low and high output

PTJDSn

drive for the associated PTJ pin. For port J pins configured as inputs, these bits have no effect.

 

0

Low output drive strength selected for port J bit n.

 

1

High output drive strength selected for port J bit n.

 

 

 

6.7.10Keyboard Interrupt 1 (KBI1) Registers

KBI1 is controlled by the registers listed below. Table 6-52shows KBI1 pin mapping to the port I/O pins.

Table 6-52. KBI1 Pin Mapping

Port pin

PTB3

PTB2

PTB1

PTB0

PTA3

PTA2

PTA1

PTA0

 

 

 

 

 

 

 

 

 

KBI1 pin

KBI1P7

KBI1P6

KBI1P5

KBI1P4

KBI1P3

KBI1P2

KBI1P1

KBI1P0

 

 

 

 

 

 

 

 

 

6.7.10.1KBI1 Interrupt Status and Control Register (KBI1SC)

R

W

Reset:

7

6

5

4

3

2

1

0

0

0

0

0

KBF

0

KBIE

KBIMOD

 

 

 

 

 

 

 

 

 

 

 

KBACK

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

0

0

0

0

0

0

0

0

 

 

 

 

 

 

 

 

 

 

Figure 6-55. KBI1 Interrupt Status and Control Register (KBI1SC)

 

 

Table 6-53. KBI1SC Register Field Descriptions

 

 

 

Field

 

Description

 

 

7–4

Reserved, should be cleared.

 

 

3

KBI1 Interrupt Flag. KBF indicates when a KBI1 interrupt is detected. Writes have no effect on KBF.

KBF

0

No KBI1 interrupt detected.

 

1

KBI1 interrupt detected.

 

 

2

KBI1 Interrupt Acknowledge. Writing a 1 to KBACK is part of the flag clearing mechanism. KBACK always reads

KBACK

as 0.

 

 

1

KBI1 Interrupt Enable. KBIE determines whether a KBI1 interrupt is requested.

KBIE

0

KBI1 interrupt request not enabled.

 

1

KBI1 interrupt request enabled.

 

 

0

KBI1 Detection Mode. KBIMOD (along with the KBI1ES bits) controls the detection mode of the KBI1 interrupt

KBIMOD

pins.

 

0

KBI1 pins detect edges only.

 

1

KBI1 pins detect edges and levels.

 

 

 

MCF51QE128 MCU Series Reference Manual, Rev. 3

140

Freescale Semiconductor

Get the latest version from freescale.com

Page 140
Image 140
Freescale Semiconductor MCF51QE128RM manual Keyboard Interrupt 1 KBI1 Registers, Ptjds Register Field Descriptions