at90ls8535-8mi ATMEL Corporation, at90ls8535-8mi Datasheet - Page 5

• Manufacturer Part Number: at90ls8535-8mi
• Description: 8-bit Microcontroller With 8k Bytes In-system Programmable Flash
• Manufacturer: ATMEL Corporation

Port D (PD7..PD0)
RESET
XTAL1
XTAL2
AVCC
AREF
AGND
1041H–11/01
current if the pull-up resistors are activated. Two Port C pins can alternatively be used
as oscillator for Timer/Counter2.
The Port C pins are tri-stated when a reset condition becomes active, even if the clock is
not running.
Port D is an 8-bit bi-directional I/O port with internal pull-up resistors. The Port D output
buffers can sink 20 mA. As inputs, Port D pins that are externally pulled low will source
current if the pull-up resistors are activated.
Port D also serves the functions of various special features of the AT90S8535 as listed
on page 86.
The Port D pins are tri-stated when a reset condition becomes active, even if the clock is
not running.
Reset input. An external reset is generated by a low level on the RESET pin. Reset
pulses longer than 50 ns will generate a reset, even if the clock is not running. Shorter
pulses are not guaranteed to generate a reset.
Input to the inverting oscillator amplifier and input to the internal clock operating circuit.
Output from the inverting oscillator amplifier.
AVCC is the supply voltage pin for Port A and the A/D Converter. If the ADC is not used,
this pin must be connected to VCC. If the ADC is used, this pin must be connected to
VCC via a low-pass filter. See page 68 for details on operation of the ADC.
AREF is the analog reference input for the A/D Converter. For ADC operations, a volt-
age in the range 2V to AV
Analog ground. If the board has a separate analog ground plane, this pin should be con-
nected to this ground plane. Otherwise, connect to GND.
CC
must be applied to this pin.
AT90S/LS8535
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