LCD BARgraphs

[ChrisMicro]

This is my version of the bar graph.

'****************************************************************
'*  Name    : Bargraph.BAS                                      *
'*  Author  : Chris Bezuidenhout                                *
'*  Notice  : Copyright (c) 2005 Micro Developments             *
'*          : All Rights Reserved                               *
'*  Date    : 2005/07/19                                        *
'*  Version : 1.0                                               *
'*  URL     : http://www.patenttrade.net                        *
'*  E-mail  : [email protected]                             *
'*  Mobile  : +27-72-795-0107                                   *
'*  Notes   : This is a bargraph demo for a 2X20 LCD Display    *
'*          : it is free to use and distribute by any one       *
'*          : as long as this Copyright note is not altered or  *
'*          : removed, can be used as an analog meter.          *
'*  Device  : PIC16F877 can be altered to work on other devices *
'****************************************************************
	INCLUDE "Modedefs.Bas"

DEFINE 	OSC 4		' Set Xtal Frequency 		
DEFINE LCD_DREG PORTA     ' Set LCD Data port
DEFINE LCD_DBIT 0         ' Set starting Data BIT (0 OR 4) IF 4-BIT bus
DEFINE LCD_RSREG PORTA    ' Set LCD Register Select port               
DEFINE LCD_RSBIT 4        ' Set LCD Register Select BIT                
DEFINE LCD_EREG PORTE     ' Set LCD Enable port, for other devices, use PORT A or B                           
DEFINE LCD_EBIT 0         ' Set LCD Enable BIT                         
DEFINE LCD_BITS 4         ' Set LCD bus side (4 OR 8 bits)             
DEFINE LCD_LINES 2        ' Set number of lines ON LCD

' md Declare the Variables md

	counter		VAR		BYTE
	Text		VAR		BYTE[20]
	X			VAR		BYTE
	Y			VAR		BYTE
PAUSE 500
Main:	
'*********Modefy first 5 characters in LCD character generator to display bargraph**********
		LCDOut $fe,%1000000           'SET CG RAM ADD.
		FOR X =1 TO 8                 
		LCDOUT %10000
		next x
		FOR X=1 TO 8
		LCDOUT %11000
		NEXT X
		FOR X=1 TO 8
		LCDOUT %11100
		NEXT X
		FOR X=1 TO 8
		LCDOUT %11110
		NEXT X
		FOR X=1 TO 8
		LCDOUT %11111
		NEXT X
		LCDOut $fe,%10000000             'SET DD RAM ADD.
'		FOR X = 0 TO 255
'		LCDOUT $FE,1,#X,X
'		PAUSE 100
'		NEXT X
LOOP1:		LCDOUT $FE,1,"This is a test"
		
		LCDOUT $FE,$C0          'clear second line and display bar graph
		LCDOUT 0                'print first character
		for X= 0 TO 19	        'change 19 to 15 for 16 character display
		PAUSE 100
		LCDOUT $FE,$10,1        'move curser back and overprint previous character
		PAUSE 100
		LCDOUT $FE,$10,2        'move curser back and overprint previous character
		PAUSE 100
		LCDOUT $FE,$10,3        'move curser back and overprint previous character
		PAUSE 100
		LCDOUT $FE,$10,4        'move curser back and overprint previous character
		PAUSE 100
		LCDOUT $FE,$14          'print next character
		LCDOUT $FE,0
		NEXT X

 		
 		GOTO LOOP1
		
 END

[Darrel Taylor]

Chris,

The Note says "can be used as an analog meter".

How would you do that?
<br>

[tenaja]

It's a slight variation of Les Johnson's bargraph routine, which is in his PBP book. You load the "graphics" of the bar graph into lcd memory, then print solid bars (or blocks) until the final one which is printed as the mod of 3. The above bar graphs use a resolution of five, which has the disadvantage of a space between each five. Les' uses three, because it makes the space between the characters an unnoticed and integral part of the graph. If you don't have Les' book, then look for one of the Proton samples, because they ship with it.

[ChrisMicro]

Chris,

The Note says "can be used as an analog meter".

How would you do that?
<br>

You have to use a chip with AD channels like the 16F818/819 then say for 1 volt you send your 5th character and for 1.4 volt you will send the 5th and the second character for 2.2 volt you will send the 5th character twice and then your first character so your 5th character is your integer and the first four is your decimals after the point, it give you a .2 resolution .2, .4, .6, .8

[ChrisMicro]

You can even draw little 5X7 sprites, like a walking man or any 5X7 picture. I have a small basic compiler with some handy tools, where you can create the picture and get the data for your picture. there is also a seven segment tool, it is free to download from my site, but you can only use the compiler with the programmer from Mikro Elektronika, but the tools is handy. look in the right border for free downloads it is the first item