XC908AS60ACFU Motorola Semiconductor Products, XC908AS60ACFU Datasheet - Page 434
XC908AS60ACFU
Manufacturer Part Number
XC908AS60ACFU
Description
MC68HC908AZ60A, MC68HC908AS60A Hcmos Microcontroller Unit Technical Data
Manufacturer
Motorola Semiconductor Products
Datasheet
1.XC908AS60ACFU.pdf
(576 pages)
- Current page: 434 of 576
- Download datasheet (4Mb)
Keyboard Module (KBD)
Technical Data
434
If the MODEK bit is set, the keyboard interrupt pins are both falling edge-
and low level-sensitive, and both of the following actions must occur to
clear a keyboard interrupt request:
The vector fetch or software clear and the return of all enabled keyboard
interrupt pins to logic 1 may occur in any order.
If the MODEK bit is clear, the keyboard interrupt pin is falling edge-
sensitive only. With MODEK clear, a vector fetch or software clear
immediately clears the keyboard interrupt request.
Reset clears the keyboard interrupt request and the MODEK bit, clearing
the interrupt request even if a keyboard interrupt pin stays at logic 0.
The keyboard flag bit (KEYF) in the keyboard status and control register
can be used to see if a pending interrupt exists. The KEYF bit is not
affected by the keyboard interrupt mask bit (IMASKK) which makes it
useful in applications where polling is preferred.
To determine the logic level on a keyboard interrupt pin, use the data
direction register to configure the pin as an input and read the data
register.
•
•
Vector fetch or software clear — A vector fetch generates an
interrupt acknowledge signal to clear the interrupt request.
Software may generate the interrupt acknowledge signal by
writing a logic 1 to the ACKK bit in the keyboard status and control
register (KBSCR). The ACKK bit is useful in applications that poll
the keyboard interrupt pins and require software to clear the
keyboard interrupt request. Writing to the ACKK bit prior to leaving
an interrupt service routine also can prevent spurious interrupts
due to noise. Setting ACKK does not affect subsequent transitions
on the keyboard interrupt pins. A falling edge that occurs after
writing to the ACKK bit latches another interrupt request. If the
keyboard interrupt mask bit, IMASKK, is clear, the CPU loads the
program counter with the vector address at locations $FFDE and
$FFDF.
Return of all enabled keyboard interrupt pins to logic 1. As long as
any enabled keyboard interrupt pin is at logic 0, the keyboard
interrupt remains set.
Keyboard Module (KBD)
MC68HC908AZ60A — Rev 2.0
MOTOROLA
Related parts for XC908AS60ACFU
Image
Part Number
Description
Manufacturer
Datasheet
Request
R
Part Number:
Description:
Triacs
Manufacturer:
Motorola Semiconductor Products
Datasheet:
Part Number:
Description:
Triacs
Manufacturer:
Motorola Semiconductor Products
Datasheet:
Part Number:
Description:
6367254 Motorola SC (xstrs/r F)
Manufacturer:
Motorola Semiconductor Products
Datasheet:
Part Number:
Description:
50 Amperes NPN Silicon Power Darlington Transistor 850 Volts 250 Watts
Manufacturer:
Motorola Semiconductor Products
Datasheet:
Part Number:
Description:
M68HC12B Family Data Sheet
Manufacturer:
Motorola Semiconductor Products
Datasheet:
Part Number:
Description:
DUAL GATE Mosfet VHF Amplifier
Manufacturer:
Motorola Semiconductor Products
Datasheet:
Part Number:
Description:
DUAL GATE Mosfet VHF Amplifier
Manufacturer:
Motorola Semiconductor Products
Datasheet:
Part Number:
Description:
NPN Darlington Silicon Power Transistor 10 Amperes 80 Volts 20 Watts
Manufacturer:
Motorola Semiconductor Products
Datasheet:
Part Number:
Description:
Integrated Circuits
Manufacturer:
Motorola Semiconductor Products
Datasheet:
Part Number:
Description:
Low Skew CMOS Clock Driver
Manufacturer:
Motorola Semiconductor Products
Datasheet:
Part Number:
Description:
Low Skew CMOS Clock Driver With Reset
Manufacturer:
Motorola Semiconductor Products
Datasheet:
Part Number:
Description:
Manufacturer:
Motorola Semiconductor Products
Datasheet:
Part Number:
Description:
Low-cost 16-bit DSP with DDR Controller and 10/100 Mbps Ethernet MAC
Manufacturer:
Motorola Semiconductor Products
Datasheet:
Part Number:
Description:
Fast Recovery Power Rectifiers
Manufacturer:
Motorola Semiconductor Products
Datasheet: