
System Overview
3-17
defaults to a PIO input with pullup, so the pin does not need to be driven
High externally.
SRDY/PIO6
Synchronous Ready (input, synchronous, level-sensitive)
This pin indicates to the microcontroller that the addressed memory
space or I/O device will complete a data transfer. The SRDY pin accepts
an active High input synchronized to CLKOUTA.
Using SRDY instead of ARDY allows a relaxed system timing because
of the elimination of the one-half clock period required to internally
synchronize ARDY. To always assert the ready condition to the
microcontroller, tie SRDY High. If the system does not use SRDY, tie
the pin Low to yield control to ARDY.
TMRIN0/PIO11
Timer Input 0 (input, synchronous, edge-sensitive)
This pin supplies a clock or control signal to the internal microcontroller
timer 0. After internally synchronizing a Low-to-High transition on
TMRIN0, the microcontroller increments the timer. TMRIN0 must be
tied High if not being used. When PIO11 is enabled, TMRIN0 is pulled
High internally.
TMRIN0 is driven internally by INT2/INTA0/PWD when pulse width
demodulation mode is enabled. The TMRIN0/PIO11 pin can be used
as a PIO when pulse width demodulation mode is enabled.
TMRIN1/PIO0
Timer Input 1 (input, synchronous, edge-sensitive)
This pin supplies a clock or control signal to the internal microcontroller
timer 1. After internally synchronizing a Low-to-High transition on
TMRIN1, the microcontroller increments the timer. TMRIN1 must be
tied High if not being used. When PIO0 is enabled, TMRIN1 is pulled
High internally.
TMRIN1 is driven internally by INT2/INTA0/PWD when pulse width
demodulation mode is enabled. The TMRIN1/PIO0 pin can be used as
a PIO when pulse width demodulation mode is enabled.
TMROUT0/PIO10 Timer Output 0 (output, synchronous)
This pin supplies the system with either a single pulse or a continuous
waveform with a programmable duty cycle. TMROUT0 is floated during
a bus hold or reset.
TMROUT1/PIO1
Timer Output 1 (output, synchronous)
This pin supplies the system with either a single pulse or a continuous
waveform with a programmable duty cycle. TMROUT1 floats during a
bus hold or reset.
TXD0/PIO22
Transmit Data 0 (output, asynchronous)
This pin supplies asynchronous serial transmit data to the system from
serial port 0.
TXD1/PIO27
Transmit Data 1 (output, asynchronous)
This pin supplies asynchronous serial transmit data to the system from
serial port 1.
Содержание Am186 ES
Страница 1: ...Am186 ES and Am188 ES User s Manual...
Страница 4: ...iv...
Страница 12: ...Table of Contents xii...
Страница 22: ...Features and Performance 1 8...
Страница 60: ...System Overview 3 28...
Страница 84: ...Chip Select Unit 5 14...
Страница 132: ...Timer Control Unit 8 8...
Страница 166: ...Programmable I O Pins 11 6...
Страница 184: ...Register Summary A 18...