PWM Module for Swordfish
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This module implements a simple modulo-based
PSEUDO Random Number Generator for Swordfish Basic. It's difficult
to generate true random numbers from a deterministic machine like
PIC. Hopefully, some mathematical methods let us have a series of
numbers that seems really random, although they have all a fixed
cycle upon which they restart to give the same series of values.
this is why they are all called Pseudo random number generators. The
cycling behaviour has the advantage to give you the possibility to
repeat the same experience despite the fact that it's based on
(pseudo) random numbers.
Usage
example
Call the
RandGen.Initialize(pInitialValue)
one time with the initial value (value read from an analogue
floating PIC pin for example).
Call the
RandGen.Rand()
function to get a new random value.
The following program gives an example on
how to use the pseudo-random number generator.
Variable Frequency PWM Example
Device
= 18F4620
Clock = 20
Include "usart.bas"
Include "convert.bas"
Include "RandGen.bas"
Dim RandomNumber As
Byte
SetBaudrate(br9600)
// initialize the generator Initial Seed Value
to 2
// for Full Random value you can use an ADC
read on
// a floating AN PIC Pin
RandGen.Initialize(2)
TRISB = 0 'All output
While true
// generates a number
RandomNumber = RandGen.Rand()
// write to RS233
Write(DecToStr(RandomNumber),13,10)
// visualise number on PORTB leds (on my
EasyPic Board)
LATB = RandomNumber
DelayMS(600)
Wend
Written by
Ahmed Lazreg (octal). A simple Pseudo Random Number Generator
module (modulo based).
Link:
What is a Swordfish Library?
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