z8f083a ZiLOG Semiconductor, z8f083a Datasheet - Page 51

• Manufacturer Part Number: z8f083a
• Description: High-performance 8-bit Microcontrollers
• Manufacturer: ZiLOG Semiconductor

Direct LED Drive
Shared Reset Pin
Crystal Oscillator Override
5 V Tolerance
PS026308-1207
The Port C pins provide a sinked current output, capable of driving an LED without
requiring an external resistor. The output sinks current at programmable levels of 3 mA,
7 mA, 13 mA, and 20 mA. 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. For details on maximum total current for the applicable package, see
Electrical Characteristics
On the 20- and 28-pin devices, the Port D0 pin shares function with a bidirectional reset
pin. Unlike all other I/O pins, this pin does not default to GPIO function on power-up.
This pin acts as a bidirectional reset until the user software re-configures it. When in GPIO
mode, the Port D0 pin functions as output only.
For systems using a crystal oscillator, the pins PA0 and PA1 are connected to the crystal.
When the crystal oscillator is enabled, the GPIO settings are overridden and PA0 and PA1
are disabled. See
In the 20- and 28-pin versions of this device, any pin, which shares functionality with an
ADC, crystal or comparator port is not 5 V tolerant, including PA[1:0], PB[5:0] and
PC[2:0]. All other signal pins are 5 V tolerant and safely handles inputs higher than V
even with the pull-ups enabled, but with excess power consumption on pull-up resistor.
Oscillator Control Register Definitions
on page 177.
on page 148.
Z8 Encore!
DD
General Purpose Input/Output
and the cathode to the
Product Specification
®
F083A Series
DD
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