Pullup Port; Interrupt Port; Port A - Motorola DragonBall MC68328 User Manual

MPU Bus
IRQ OR
Bit IRQ
The interrupt port generates 9 interrupt signals. The individual port bits generate 8 of the
interrupts. One interrupt is the logical-OR of all 8 bits. The individual interrupt bits can be
masked on a bit-by-bit basis. The OR interrupt must be enabled or disabled in the interrupt
module. Refer to the interrupt controller block (Section 2.3) for more information. Individual
interrupts can be configured as edge- or level-sensitive, and the polarity can be selected.

7.1.2 Port A

Port A is multiplexed with address lines A16-A23. Unused address pins can serve as parallel
I/Os on a bit-by-bit basis. After reset, these signals default to their address function. Three
MOTOROLA MC68328 DRAGONBALL PROCESSOR USER'S MANUAL
PULLUP
Data to
module
Data from
module
DATA
MPU bus
Output Enable
from module
DIRECTION
SELECT
Figure 7-2. Pullup Port
PULLUP
IRQ EDGE
POLARITY
IRQ EN
DATA
DIRECTION
Figure 7-3. Interrupt Port
PAD BUFFER
0
1
SEL
0
1
SEL
SEL
0
EDGE
1
DETECT
PAD BUFFER
Parallel Ports
PAD
PAD
7-3