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Freescale Semiconductor
Application Note
Document Number: AN3949
Rev. 1, 04/2010
Contents
© Freescale Semiconductor, Inc., 2009. All rights reserved.
1 Introduction
The MCF51EM256 ColdFire MCU has an integrated
16-bit ADC and a programmable delay block (PDB).
The integration of these modules is not standardized
across different devices. The device integration of these
modules is customized for each MCU family to better
suit the needs of the targeted application.
This document describes the procedure required to
perform the analog-to-digital converter (ADC)
auto-calibration function and provides software that may
be used as a template for application code development.
The second section of this application note describes the
integration of the ADC16 and PDB peripherals for the
MCF51EM256 MCU to complement the block-specific
information provided in the reference manual. It also
describes how to use these modules together in a simple
application and synchronize them.
1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
2 ADC16 Calibration. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
2.1 Calibration Flow. . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
2.2 Calibration Latency . . . . . . . . . . . . . . . . . . . . . . . . . 6
3 ADC16 and Programmable Delay Block (PDB) Integra . 6
3.1 Trigger Timings . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
4 ADC16 and Programmable Delay Block (PDB) Synch . 10
4.1 Scheduling Conversions . . . . . . . . . . . . . . . . . . . . 10
4.2 Synchronizing . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
4.3 Monitoring Correct Operation . . . . . . . . . . . . . . . . 14
5 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
6 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
ADC16 Calibration Procedure and
Programmable Delay Block
Synchronization
For the MCF51EM256
by: Inga Harris
Applications Engineer
East Kilbride, U.K.