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On Time RTOS-32 Documentation

Welcome

RTTarget-32

RTKernel-32

RTKernel-32 Programming Manual

Introduction

Multitasking, Real-Time, and RTKernel-32

Module RTKernel-32

Alternate APIs for RTKernel-32

Supplemental Modules

RTKernel-32 Drivers

System Interface

Interrupt Handling

Kernel Clock

High Resolution Timer

Driver HRTNULL

Driver HRTPC

Driver CLKHRTPC

Driver HRTPENT

Driver HRTSC520

Driver HRTPM

Driver HRTHPET

Driver HRTVMF

Floating Point

Memory Management

Source Code Positions

CPU

Overview of all Drivers

Preconfigured Driver Library Drvrt32.lib

Demo Programs

Advanced Topics

Typical Error Sources

Error and Information Messages

RTKernel-32 Reference Manual

RTFiles-32

RTIP-32

RTPEG-32

RTUSB-32
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Driver HRTPM

The ACPI Power Management Timer is available on all ACPI systems. It runs with a rate of 3.579545 MHz (about 0.279 microseconds resolution). If no ACPI BIOS is found at run time, the Pentium Time Stamp Counter is used instead and this driver behaves exactly as the HRTPENT driver.

Unfortunately, the ACPI PM Timer must be read using port I/O which makes this driver slower than the HRTPENT driver (though it is still much faster than the default CLKHRTPC or HRTPC driver).

Due to the limited range of the ACPI PM Timer, applications must read the timer using FTReadTime at least once every 2 seconds while a time period is being measured.

Requirements: Intel Pentium or higher CPU, ACPI BIOS. Incompatible with clock driver CLKHRTPC.

LeftHigh Resolution Timer

UpDriver HRTSC520

DownDriver HRTHPET

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