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APPLICATION NOTES

AN1057/D Selecting the Right Microcontroller Unit
Selecting the proper microcontroller unit (MCU) for your application is one of the critical decisions which control the success or failure of your project. There are numerous criteria to consider when choosing an MCU and this application note will enumerate most of them. It presents an outline of the thought process guiding this decision.
The reader must attach their own grading scale to the selection criteria presented and then evaluate the total to make the correct personal decision.

AN1215/D PID Routines for MC68HC11K4 and MC68HC11N4 Microcontrollers
This note provides two working examples of PID control-loop software. The first example, written primarily in C, shows a PID algorithm in a straightforward way using floating-point math. Key features of the C environment are covered for readers who are more used to assembly language. The second example implements a PID algorithm in assembly language. It uses the MC68HC11N4 on-chip math coprocessor to speed up arithmetic operations.

AN1237/D Using M68HC11 Microcontrollers with WSI Programmable Peripheral Devices
Following system development using M68HC711 microcontroller (MCU) devices with EPROM or one time programmable ROM (OTPROM), a final design is often implemented using an equivalent mask-programmed M68HC11 device. However, there is a quick, cost-effective alternative to this method of going to production.
A “twin chip” solution with a WSI PSD device can increase flexibility, provide expanded memory and enhanced I/O, lower power consumption, and lower cost — all with a minimum of software and hardware modifications. This application note describes the process of converting from a prototype design that uses an M68HC711 device to a production design that uses a low-cost M68HC11 derivative and a WSI PSD.

AN1283/D Transporting M68HC11 Code to M68HC16 Devices
This note is intended to assist programmers who wish to transport code from the M68HC11 CPU to the CPU16. It compares the capabilities of the two processors, provides information concerning differences in the respective instruction sets, and discusses cases that need special attention. For more detailed information, please refer to the M68HC11 Reference Manual (M68HC11RM/AD) and to the CPU16 Reference Manual (CPU16RM/AD).

AN1597/D Longwave Radio Data Decoding using an HC11 and an MC3371
The BBC’s Radio 4 198 kHz Longwave transmitter carries data as well as the audio signal. This has some similarities with the RDS data included in VHF radio signals in many European countries but has a much lower data rate and is used for a different purpose. Typical uses are electricity tariff switching, foreign exchange rate board updating and lighting control. Time data is transmitted every minute on the minute and provides a very accurate clock, traceable to national standards. In this application, time and date can be permanently displayed whilst all incoming data can be displayed in hexadecimal form.The microprocessor used for decoding is the MC68HC(7)11 while an MC3371 is used for the radio receiver.