# Microcontrollers: From Assembly Language to C Using the PIC24 Family – Chapter 8 Example 5

I enjoyed this example as it’s interfacing between the user and the MCU via a computer. It also showed some interesting concepts on power management within source code.

I did notice this time I needed to use a different approach to telling the compiler I’m using the Explorer16. For some reason, it would not maintain the setting using the pre-programmer directive. So open up the file include\pic24_all.h and right at the start of the code, add the directive

#define EXPLORER16_100P

Here is the snippit of the file.

// Documentation for this file. If the \file tag isn't present,
// this file won't be documented.
/** \file
* This header file includes the all the pic24_*.h files as detailed
* in the \ref index and also includes the necessary
* processor-specific include file (via a \#include p24h/fxxxx.h).
*/
// Added this define as I'm using the Explorer16 for these examples.
#define EXPLORER16_100P
#ifndef _PIC24_ALL_H_
#define _PIC24_ALL_H_

#if defined(__PIC24H__)