Z8F082A28100KIT ZILOG [Zilog, Inc.], Z8F082A28100KIT Datasheet - Page 51

• Manufacturer Part Number: Z8F082A28100KIT
• Description: Z8 Encore XP-R F08xA Series with eXtended Peripherals
• Manufacturer: ZILOG [Zilog, Inc.]

Direct LED Drive
Shared Reset Pin
Crystal Oscillator Override
5V Tolerance
External Clock Setup
PS024705-0405
The Port C pins provide a current sinked output capable of driving an LED without requir-
ing an external resistor. The output sinks current at programmable levels of 3mA, 7mA,
13mA and 20mA. This mode is enabled through the Alternate Function sub-register AFS1
and is programmable through the LED control registers.
For correct function, the LED anode must be connected to V
GPIO pin.
Using all Port C pins in LED drive mode with maximum current may result in excessive
total current. Refer to the
current for the applicable package.
On the 20 and 28-pin devices, the Port D0 pin shares function with a bi-directional reset
pin. Unlike all other I/O pins, this pin does not default to GPIO function on power-up.
This pin acts as a bi-directional reset until user software re-configures it. The Port D0 pin
is output-only when in GPIO mode.
For systems using a crystal oscillator, PA0 and PA1 are used to connect the crystal. When
the crystal oscillator is enabled (see
the GPIO settings are overridden and PA0 and PA1 are disabled.
In the 20- and 28-pin versions of this device, any pin which shares functionality with an
ADC, crystal or comparator port is not 5V-tolerant, including PA[1:0], PB[5:0] and
PC[2:0]. All other signal pins are 5V-tolerant, and can safely handle inputs higher than
V
For systems using an external TTL drive, PB3 is the clock source for 20- and 28-pin
devices. In this case, configure PB3 for alternate function CLKIN. Write the Oscillator
Control Register (page 163) such that the external oscillator is selected as the system clock
For 8-pin devices use PA1 instead of PB3.
DD
even with the pull-ups enabled.
“Electrical Characteristics” on page 191
P R E L I M I N A R Y
“Oscillator Control Register Definitions” on page 163
Z8 Encore! XP
DD
and the cathode to the
Product Specification
for the maximum total
General-Purpose I/O
®
F08xA Series
),
33