Rainbow Electronics ATtiny2313 - Manual (Page 4)

4
ATtiny2313
2543A–AVR–08/03
Pin Descriptions
VCC Digital supply voltage.
GND Ground.
Port A (PA2..PA0) Port A is a 3-bit bi-directional I/O port with internal pull-up resistors (selected for each
bit). The Port A output buffers have symmetrical drive characteristics with both high sink
and source capability. As inputs, Port A pins that are externally pulled low will source
current if the pull-up resistors are activated. The Port A pins are tri-stated when a reset
condition becomes active, even if the clock is not running.
Port A also serves the functions of various special features of the ATtiny2313 as listed
on page 54.
Port B (PB7..PB0) Port B is an 8-bit bi-directional I/O port with internal pull-up resistors (selected for each
bit). The Port B output buffers have symmetrical drive characteristics with both high sink
and source capability. As inputs, Port B pins that are externally pulled low will source
current if the pull-up resistors are activated. The Port B pins are tri-stated when a reset
condition becomes active, even if the clock is not running.
Port B also serves the functions of various special features of the ATtiny2313 as listed
on page 54.
Port D (PD6..PD0) Port D is a 7-bit bi-directional I/O port with internal pull-up resistors (selected for each
bit). The Port D output buffers have symmetrical drive characteristics with both high sink
and source capability. As inputs, Port D pins that are externally pulled low will source
current if the pull-up resistors are activated. The Port D pins are tri-stated when a reset
condition becomes active, even if the clock is not running.
Port D also serves the functions of various special features of the ATtiny2313 as listed
on page 57.
RESET Reset input. A low level on this pin for longer than the minimum pulse length will gener-
ate a reset, even if the clock is not running. The minimum pulse length is given in Table
15 on page 35. Shorter pulses are not guaranteed to generate a reset. The Reset Input
is an alternate function for PA2 and dW.
XTAL1 Input to the inverting Oscillator amplifier and input to the internal clock operating circuit.
XTAL1 is an alternate function for PA0.
XTAL2 Output from the inverting Oscillator amplifier. XTAL2 is an alternate function for PA1.
About Code
Examples
This documentation contains simple code examples that briefly show how to use various
parts of the device. These code examples assume that the part specific header file is
included before compilation. Be aware that not all C compiler vendors include bit defini-
tions in the header files and interrupt handling in C is compiler dependent. Please
confirm with the C compiler documentation for more details.
Disclaimer
Typical values contained in this data sheet are based on simulations and characteriza-
tion of other AVR microcontrollers manufactured on the same process technology. Min
and Max values will be available after the device is characterized.