LCD and "count": need to clear LCD?

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- 22nd October 2006, 21:23
Mugel

LCD and "count": need to clear LCD?

Hi You all!

had a VERY small program using "count" and "LCDout" . Problem occurs at the display:
Every time the value displayed on the LCD goes down from two digits to one or from three to two it keeps the first number which isn´t cleared.
Going up works fine because it overwrites every digit, but going down keeps some old ones.
So I put in the "Clear Display" command into the loop but that makes the whole display flashing...otherwise the frequency counter works fine for me.

How can I clear the numbers of my value on the display without flashing the whole thing?

'
' DEFINITIONS
'
Cnt VAR Word ' Cnt is a word variable
'
' START OF MAIN PROGRAM
'
CMCON = 7 ' RA0-RA3 are digital I/O
TRISA = 0 ' PORT A is output
TRISB = 1 ' PORT B0 is input others output

PAUSE 500 ' Wait 0.5 second to initialize LCD
Cnt = 0 ' Clear Cnt to zero
LCDOUT $FE,1 ' Clear LCD
LCDOUT $FE,2
RPT:
cnt = 0
LCDOUT $FE,1 ' here is my problem!! makes everything flashing!'

LCDOUT $FE,2

Count PORTB.0,1000,CNT
LCDOUT "Freq.= ",$FE,$C0,DEC Cnt ' Display count
PAUSE 1000

Goto RPT

END
- 22nd October 2006, 21:34
sayzer

If I understood what you wanted to do, this should be it.

Code:

RPT: Count PORTB.0,1000,CNT LCDOUT $fe,1, "Freq.= ", DEC Cnt ' Display count Goto RPT

Also, no need for PAUSE 1000 because your Count command itself creates 1000ms delay for LCD.

--------------------
- 22nd October 2006, 22:55
paul borgmeier

Try somethinbg like this:

Code:

LCDOUT "Freq.= ",$FE,$C0,DEC Cnt ' Display count If Cnt < 100 then LCDOUT " " ' if Cnt is less than 100 then print a blank If Cnt < 10 then LCDOUT " " ' if Cnt is less than 10 then print a blank PAUSE 1000
- 23rd October 2006, 09:20
Acetronics2

The clear pencil

Quote:

Originally Posted by Mugel

Hi You all!

How can I clear the numbers of my value on the display without flashing the whole thing?

END

Hi,

Just print blank characters ( or new characters) UPON the existing you want to clear ...

see manual page 94, middle ...

LCDOUT $FE, $80 ( or $C0 ) + 6 ( or 7 i.e. ! ) , "___" ( 3 blanks or 888 i.e. )

$FE,$80 + 6 sets the cursor position ... to the 6th position, line 1
$FE,$C0 + 8 ................................... to the 8th position, line 2
...
...

Alain
- 23rd October 2006, 09:55
sayzer

Nice example Alain.

Also, DEC modifier can be useful, too. Like DEC3 CNT or DEC4 CNT etc...