More than 8 Custom Chars on LCD?

**Jerson** · - 9th June 2010, 08:46

Is there a way to accomplish the goal of forcing the LCD to show the digits 0-9 with double height?

The answer is NO. Not more than 4 unique double height digits at a time. Optionally, use a graphic LCD.

**Art** · - 9th June 2010, 12:15

The double line high digits use a series of blocks that only consume the eight custom characters:
http://www.doc.ic.ac.uk/~ih/doc/lcd/double.html
so you can display as many digits as the display can show.

You still couldn't make the font very detailed like you probably wanted to.

**Jerson** · - 9th June 2010, 12:35

Art, thanks for the link. I take back my words. I stand corrected.

**prstein** · - 9th June 2010, 14:20

Art,

Thanks! That was *exactly* what I needed. Here's a (low-quality) picture of the result:

Name: Big_Num_LCD.jpg
Views: 3372
Size: 54.2 KB

Complete code:

Code:

' PIC18F2550

'Pin Assignments
'---------------
' Pin	Name	           Use/Connection
'------------------------------------
'  1  MCLR			Master Clear/Reset.  Pull High through 4.7k
'  2  RA0/AN0		LCD RS
'  3  RA1/AN1		LCD R/W
'  4  RA2/AN2		LCD Enable
'  5  RA3/AN3		n/c
'  6  RA4/T0CKI		n/c
'  7  RB5/AN4		n/c
'  8  Vss			Ground
'  9  OSC1			20 MHz resonator
' 10  OSC2			20 MHz resonator
' 11  RC0/T1CKI		To 32 kHz crystal
' 12  RC1/CCP2		To 32 kHz crystal
' 13  RC2/CCP1		n/c
' 14  Vusb			To USB (internal USB 3.3V voltage regulator)

' 15  RC4/D-		To USB (USB differential minus line)
' 16  RC5/D+		To USB (USB differential plus line)
' 17  RC6/TX		To MAX232
' 18  RC7/RX		To MAX232
' 19  Vss			Ground
' 20  Vdd			Voltage in (5V from USB)
' 21  RB0/INT		LCD DB0
' 22  RB1			LCD DB1
' 23  RB2			LCD DB2
' 24  RB3			LCD DB3
' 25  RB4			LCD DB4
' 26  RB5			LCD DB5
' 27  RB6			LCD DB6
' 28  RB7			LCD DB7

' Compiler directives:
Define  OSC 20
DEFINE LOADER_USED 1 'Bootloader Used
'Set receive register to receiver enabled
DEFINE HSER_RCSTA 90h
'Set transmit register to transmitter enabled, high speed BRGH
DEFINE HSER_TXSTA 24h
'Set baud rate
DEFINE HSER_BAUD 9600
DEFINE HSER_CLROERR 1 

DEFINE LCD_DREG PORTB
DEFINE LCD_DBIT 0
DEFINE LCD_RSREG PORTA
DEFINE LCD_RSBIT 0
DEFINE LCD_EREG PORTA
DEFINE LCD_EBIT 2
DEFINE LCD_BITS 8
DEFINE LCD_LINES 2
DEFINE LCD_COMMANDUS 3000
DEFINE LCD_DATAUS 200

ADCON1 = 15
CMCON = 7

TRISB = %00000000
TRISA.0 = $0
TRISA.1 = $0
TRISA.2 = $0

nPos var byte

low PORTA.1

'high PORTA.2
pause 500
LCDOUT $FE,1

'Set up the digits (http://www.darreltaylor.com/files/CustChar.htm)
LCDOUT  $FE,$40,$01,$01,$01,$01,$01,$01,$01,$01  ' Cust Char #0 
'LCDOUT  $FE,$40,$02,$02,$02,$02,$02,$02,$02,$02  ' Cust Char #0   
LCDOUT  $FE,$48,$1F,$11,$11,$11,$11,$11,$11,$11  ' Cust Char #1  
LCDOUT  $FE,$50,$1F,$10,$10,$10,$10,$10,$10,$1F  ' Cust Char #2  
LCDOUT  $FE,$58,$01,$01,$01,$01,$01,$01,$01,$1F  ' Cust Char #3  
LCDOUT  $FE,$60,$1F,$11,$11,$11,$11,$11,$11,$1F  ' Cust Char #4  
LCDOUT  $FE,$68,$11,$11,$11,$11,$11,$11,$11,$1F  ' Cust Char #5  
LCDOUT  $FE,$70,$1F,$01,$01,$01,$01,$01,$01,$1F  ' Cust Char #6  
LCDOUT  $FE,$78,$1F,$01,$01,$01,$01,$01,$01,$01  ' Cust Char #7  
  
GOTO MAIN_LOOP

Zero:
	LCDOUT $FE,$80+nPos,1
	LCDOUT $FE,$C0+nPos,5
return

One:
	LCDOUT $FE,$80+nPos,0
	LCDOUT $FE,$C0+nPos,0
return

Two:
	LCDOUT $FE,$80+nPos,7
	LCDOUT $FE,$C0+nPos,2
return

Three:
	LCDOUT $FE,$80+nPos,6
	LCDOUT $FE,$C0+nPos,3
return

Four:
	LCDOUT $FE,$80+nPos,5
	LCDOUT $FE,$C0+nPos,0
return

Five:
	LCDOUT $FE,$80+nPos,2
	LCDOUT $FE,$C0+nPos,3
return

Six:
	LCDOUT $FE,$80+nPos,2
	LCDOUT $FE,$C0+nPos,5
return

Seven:
	LCDOUT $FE,$80+nPos,7
	LCDOUT $FE,$C0+nPos,0
return

Eight:
	LCDOUT $FE,$80+nPos,4
	LCDOUT $FE,$C0+nPos,5
return

Nine:
	LCDOUT $FE,$80+nPos,4
	LCDOUT $FE,$C0+nPos,3
return

MAIN_LOOP:
	nPos = 0
	GOSUB Zero
	nPos = 1
	GOSUB One
	nPos = 2
	GOSUB Two
	nPos = 3
	GOSUB Three
	nPos = 4
	GOSUB Four
	nPos = 5
	GOSUB Five
	nPos = 6
	GOSUB Six
	nPos = 7
	GOSUB Seven
	nPos = 8
	GOSUB Eight
	nPos = 9
	GOSUB Nine

	PAUSE 2000
GOTO MAIN_LOOP

And thanks to everyone else for reading and commenting. You folks are the best...

Best Regards,
Paul

**Art** · - 10th June 2010, 08:51

Wow, it looks a lot nicer on the LCD than it did on the web page.

**savnik** · - 10th June 2010, 12:23

And if we have a variable byte or word how to display?

**prstein** · - 10th June 2010, 15:23

Originally Posted by savnik

And if we have a variable byte or word how to display?

Use the DIG function. The demo below counts up to 65534, showing each number for 25mS. It also blanks out any leading zeros.

Code:

' PIC18F2550

'Pin Assignments
'---------------
' Pin	Name	           Use/Connection
'------------------------------------
'  1  MCLR			Master Clear/Reset.  Pull High through 4.7k
'  2  RA0/AN0		LCD RS
'  3  RA1/AN1		LCD R/W
'  4  RA2/AN2		LCD Enable
'  5  RA3/AN3		n/c
'  6  RA4/T0CKI		n/c
'  7  RB5/AN4		n/c
'  8  Vss			Ground
'  9  OSC1			20 MHz resonator
' 10  OSC2			20 MHz resonator
' 11  RC0/T1CKI		To 32 kHz crystal
' 12  RC1/CCP2		To 32 kHz crystal
' 13  RC2/CCP1		n/c
' 14  Vusb			To USB (internal USB 3.3V voltage regulator)

' 15  RC4/D-		To USB (USB differential minus line)
' 16  RC5/D+		To USB (USB differential plus line)
' 17  RC6/TX		To MAX232
' 18  RC7/RX		To MAX232
' 19  Vss			Ground
' 20  Vdd			Voltage in (5V from USB)
' 21  RB0/INT		LCD DB0
' 22  RB1			LCD DB1
' 23  RB2			LCD DB2
' 24  RB3			LCD DB3
' 25  RB4			LCD DB4
' 26  RB5			LCD DB5
' 27  RB6			LCD DB6
' 28  RB7			LCD DB7

' Compiler directives:
Define  OSC 20
DEFINE LOADER_USED 1 'Bootloader Used
'Set receive register to receiver enabled
DEFINE HSER_RCSTA 90h
'Set transmit register to transmitter enabled, high speed BRGH
DEFINE HSER_TXSTA 24h
'Set baud rate
DEFINE HSER_BAUD 9600
DEFINE HSER_CLROERR 1 

DEFINE LCD_DREG PORTB
DEFINE LCD_DBIT 0
DEFINE LCD_RSREG PORTA
DEFINE LCD_RSBIT 0
DEFINE LCD_EREG PORTA
DEFINE LCD_EBIT 2
DEFINE LCD_BITS 8
DEFINE LCD_LINES 2
DEFINE LCD_COMMANDUS 1600'3000
DEFINE LCD_DATAUS 50'200

TRUE        	CON 1
FALSE       	CON 0

ADCON1 = 15
CMCON = 7

TRISB = %00000000
TRISA.0 = $0
TRISA.1 = $0
TRISA.2 = $0

nPos var byte
wVal var WORD
nDig var byte
bDoneWithLeadingZeros var bit

low PORTA.1

'high PORTA.2
pause 500
LCDOUT $FE,1

'Set up the digits (http://www.darreltaylor.com/files/CustChar.htm)
LCDOUT  $FE,$40,$01,$01,$01,$01,$01,$01,$01,$01  ' Cust Char #0 
LCDOUT  $FE,$48,$1F,$11,$11,$11,$11,$11,$11,$11  ' Cust Char #1  
LCDOUT  $FE,$50,$1F,$10,$10,$10,$10,$10,$10,$1F  ' Cust Char #2  
LCDOUT  $FE,$58,$01,$01,$01,$01,$01,$01,$01,$1F  ' Cust Char #3  
LCDOUT  $FE,$60,$1F,$11,$11,$11,$11,$11,$11,$1F  ' Cust Char #4  
LCDOUT  $FE,$68,$11,$11,$11,$11,$11,$11,$11,$1F  ' Cust Char #5  
LCDOUT  $FE,$70,$1F,$01,$01,$01,$01,$01,$01,$1F  ' Cust Char #6  
LCDOUT  $FE,$78,$1F,$01,$01,$01,$01,$01,$01,$01  ' Cust Char #7  
  
GOTO MAIN_LOOP

Zero:
	LCDOUT $FE,$80+nPos,1
	LCDOUT $FE,$C0+nPos,5
return

One:
	LCDOUT $FE,$80+nPos,0
	LCDOUT $FE,$C0+nPos,0
return

Two:
	LCDOUT $FE,$80+nPos,7
	LCDOUT $FE,$C0+nPos,2
return

Three:
	LCDOUT $FE,$80+nPos,6
	LCDOUT $FE,$C0+nPos,3
return

Four:
	LCDOUT $FE,$80+nPos,5
	LCDOUT $FE,$C0+nPos,0
return

Five:
	LCDOUT $FE,$80+nPos,2
	LCDOUT $FE,$C0+nPos,3
return

Six:
	LCDOUT $FE,$80+nPos,2
	LCDOUT $FE,$C0+nPos,5
return

Seven:
	LCDOUT $FE,$80+nPos,7
	LCDOUT $FE,$C0+nPos,0
return

Eight:
	LCDOUT $FE,$80+nPos,4
	LCDOUT $FE,$C0+nPos,5
return

Nine:
	LCDOUT $FE,$80+nPos,4
	LCDOUT $FE,$C0+nPos,3
return

Blank:
	LCDOUT $FE,$80+nPos," "
	LCDOUT $FE,$C0+nPos," "
return

PickDigit:
	if nDig = 0 AND bDoneWithLeadingZeros = false then
		gosub Blank
'LCDOUT $FE,1
	else
		bDoneWithLeadingZeros = true
		select case nDig
		case 0
			gosub Zero
		case 1
			gosub One
		case 2
			gosub Two
		case 3
			gosub Three
		case 4
			gosub Four
		case 5
			gosub Five
		case 6
			gosub Six
		case 7
			gosub Seven
		case 8
			gosub Eight
		case 9
			gosub Nine
		end select
	endif
return

MAIN_LOOP:
	for wVal = 0 to $FFFE 
		bDoneWithLeadingZeros = FALSE
		'Most significant digit
		nPos = 0
		nDig = wVal dig 4
		Gosub PickDigit
		
		nPos = 1
		nDig = wVal dig 3
		Gosub PickDigit
		
		nPos = 2
		nDig = wVal dig 2
		Gosub PickDigit
		
		nPos = 3
		nDig = wVal dig 1
		Gosub PickDigit
		
		'Least significant digit
		nPos = 4
		nDig = wVal dig 0
		Gosub PickDigit
		
		pause 25
	next wVal
goto MAIN_LOOP

Best Regards,
Paul

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