user manual

General Description
Signal Description
MC68HC05RC16 — Rev. 3.0 General Release Specification
MOTOROLA General Description 25
1.5.4 RESET
This active-low pin is used to reset the MCU to a known startup state by
pulling RESET low. The RESET pin contains an internal Schmitt trigger
as part of its input to improve noise immunity. See Section 5. Resets.
1.5.5 LPRST
The
LPRST pin is an active-low pin and is used to put the MCU into
low-power reset mode. In low-power reset mode the MCU is held in reset
with all processor clocks halted. See Section 5. Resets.
1.5.6 IRO
The IRO pin is the high-current source and sink output of the carrier
modulator transmitter subsystem which is suitable for driving infrared
(IR) LED biasing logic. See Section 9. Carrier Modulator Transmitter
(CMT).
1.5.7 PA0–PA7
These eight I/O lines comprise port A. The state of any pin is software
programmable and all port A lines are configured as inputs during
power-on or reset. For detailed information on I/O programming, see 2.4
Input/Output Programming.
1.5.8 PB0–PB7
These eight I/O lines comprise port B. The state of any pin is software
programmable and all port B lines are configured as inputs during
power-on or reset. Each port B I/O line has a mask optionable
pullup/interrupt for keyscan. For detailed information on I/O
programming, see 2.4 Input/Output Programming.