Z8 Encore!® Motor Control Flash MCUs
Product Specification
36
VDD
Pull-Up Enable
Analog In/Out
Alternate Function
Digital Input
On-Chip
Peripheral
Schmitt Trigger
Port Input
Data Register
Q
D
System Clock
Port Output Control
Port Output
Data Register
Data Bus
D
Q
Port
Pin
System Clock
Port Data Direction
GND
Figure 5. GPIO Port Pin Block Diagram
GPIO Alternate Functions
Many of the GPIO port pins can be used as both general-purpose I/O and to provide access
to on-chip peripheral functions, such as timers and serial communication devices. The Port
A-C Alternate Function subregisters configure these pins for either general-purpose I/O or
alternate function operation. When a pin is configured for alternate function, control of the
port pin direction (input/output) is passed from the Port A-C Data Direction registers to
the alternate function assigned to this pin. For peripherals with digital input alternate func-
tions (for example, a Timer input T0IN0), selecting the alternate function is not required.
Table 13 lists the alternate functions associated with each port pin and the required alter-
nate function (AF0 and AF1) subregister settings. In general, enabling an analog alternate
General-Purpose I/O
P R E L I M I N A R Y
PS024604-1005
ZILOG [ ZILOG, INC. ]
