MC68HC908QY4A_10 Datasheet, PDF (191/200 Pages) Freescale Semiconductor, Inc – M68HC08 Microcontrollers

Appendix A
908QTA/QYxA Conversion Guidelines
A.1 Introduction
This engineering bulletin describes the 908QTA/QYxA. The 908QTA/QYxA is an enhanced device
intended to replace the 908QT/QYx series of devices (referred to as the QY Classic in this document).
Customer requests have led to the advanced design of the QYxA that has added adaptability, new
features, and contains lead-free packaging.
This document:
• Provides information needed to convert from QY Classic to the enhanced QYxA
• Highlights the benefits of making this change
Sections:
• A.2 Benefits of the Enhanced QYxA
• A.3 Conversion Considerations
• A.4 Code Changes Checklist
• A.5 Development Tools
• A.6 Differences in Packaging
A.2 Benefits of the Enhanced QYxA
The QYxA contains new and enhanced modules that add more flexibility and new features to the QY
Classic. These benefits can improve the operation of an application or lead to new features for an
application. For more information regarding these features refer to the QYxA data sheet (Freescale
document order number MC68HC908QYxA).
A.2.1 New Analog-to-Digital Converter Module (ADC)
The QYxA contains a 10-bit ADC which replaces the 8-bit ADC on the QY Classic. This module allows
both 10-bit and 8-bit conversion modes. The increased precision for ADC readings can be very useful in
many applications.
Features of the ADC new 10-bit module include:
• There are two new ADC channels that have been placed on PTB0 and PTB1 allowing added
flexibility especially when debugging in Monitor Mode.
– A limitation of QY Classic debugging is that access to the ADC channels is limited because
many of the QY Classic pins are multiplexed. Having extra ADC channels on the PTB pins
resolves this limitation.
MC68HC908QYA/QTA Family Data Sheet, Rev. 3
Freescale Semiconductor
191