FREQUENCY GENERATOR

VCC

8XC196

Device

P7.7

Filter and

Output Signal

Detector

 

A2704-02

Figure 8-4. Infrared Remote Control Application Block Diagram

40 kHz

Zero = 2 ms

One = 4 ms

A2703-01

Figure 8-5. Data Encoding Example

This program example was designed to run on an 8XC196MD demo board. It uses an EPA timer (timer 1) and compare channel (COMP3) to provide the timebase for the ones and zeros.

$debug $nolist

$include (c:\ecm\196mc\mc.inc) $list

;

;***************************************

;PROGRAM FREQ.A96

;This program transmits a block of data serially

;by gating the frequency generator on and off.

;

;The carrier frequency is programmed for 40 kHz.

;Ones are represented by a long (2 ms) carrier burst

;followed by a long (2 ms) pause (no carrier).

;Zeros are represented by a short (1 ms) carrier burst

8-5

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Intel 8XC196MD, 8XC196MH, 8XC196MC manual Frequency Generator