MC9S08JM16 Datasheet, PDF (123/386 Pages) Freescale Semiconductor, Inc – Microcontrollers

Keyboard Interrupts (S08KBIV2)
7
6
5
4
3
2
1
0
R
0
0
0
0
KBF
0
KBIE
KBMOD
W
KBACK
Reset:
0
0
0
0
0
0
0
0
= Unimplemented
Figure 8-3. KBI Status and Control Register
Table 8-2. KBISC Register Field Descriptions
Field
Description
7:4 Unused register bits, always read 0.
3
Keyboard Interrupt Flag — KBF indicates when a keyboard interrupt is detected. Writes have no effect on KBF.
KBF 0 No keyboard interrupt detected.
1 Keyboard interrupt detected.
2
Keyboard Acknowledge — Writing a 1 to KBACK is part of the flag clearing mechanism. KBACK always reads
KBACK as 0.
1
KBIE
Keyboard Interrupt Enable — KBIE determines whether a keyboard interrupt is requested.
0 Keyboard interrupt request not enabled.
1 Keyboard interrupt request enabled.
0
Keyboard Detection Mode — KBMOD (along with the KBEDG bits) controls the detection mode of the keyboard
KBMOD interrupt pins.0Keyboard detects edges only.
1 Keyboard detects both edges and levels.
8.3.2 KBI Pin Enable Register (KBIPE)
KBIPE contains the pin enable control bits.
7
R
KBIPE7
W
Reset:
0
6
KBIPE6
5
KBIPE5
4
KBIPE4
3
KBIPE3
2
KBIPE2
0
0
0
0
0
Figure 8-4. KBI Pin Enable Register
1
KBIPE1
0
0
KBIPE0
0
Table 8-3. KBIPE Register Field Descriptions
Field
Description
7:0
KBIPEn
Keyboard Pin Enables — Each of the KBIPEn bits enable the corresponding keyboard interrupt pin.
0 Pin not enabled as keyboard interrupt.
1 Pin enabled as keyboard interrupt.
8.3.3 KBI Edge Select Register (KBIES)
KBIES contains the edge select control bits.
MC9S08JM16 Series Data Sheet, Rev. 2
Freescale Semiconductor
123