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Old 1st October 2007, 10:26 AM   (permalink)
Experienced Member
 
HerbertMunch is on a distinguished road
Default PIC16F628A LCD problems.
The following code is adapted from Nigels LCD tutorials.

Im trying to modify it so that instead of using a0-a3 for data lines, it uses b0-b3 for the data.

I thought that this would be extremely simple to implement (i.e change wires, change applicable LCD_PORT code From A to PORTB.)

For some reason though, it doesnt work!
can anyone see the problem?

I have left the code so that it writes data to both port a and portb, just so i can quickly change the wires round to see it working.

Many thanks

Code:
	LIST	p=16F628a		;tell assembler what chip we are using
	include "P16F628a.inc"		;include the defaults for the chip
	ERRORLEVEL	0,	-302	;suppress bank selection messages
	__cONFIG	_CP_OFF &_PWRTE_OFF  & _WDT_OFF &_DATA_CP_OFF & _MCLRE_OFF & _INTOSC_OSC_NOCLKOUT &_LVP_OFF

;Set led on
Led_On  Macro Led
		banksel		LED_PORT
		bsf			LED_PORT, Led
endm

;Set led off
Led_Off Macro Led
		banksel		LED_PORT
		bcf			LED_PORT, Led
		


endm

		cblock	0x20			;start of general purpose registers
			count			;used in looping routines
			count1			;used in delay routine
			counta			;used in delay routine
			countb			;used in delay routine

			temp
			delayCountA
			delayCountB
			delayCountC
			messageCounter
			tmp1			;temporary storage
			tmp2
			templcd			;temp store for 4 bit mode
			templcd2
			
        		NumL			;Binary inputs for decimal convert routine
	        	NumH	

        		TenK			;Decimal outputs from convert routine
	        	Thou	
        		Hund	
	        	Tens	
        		Ones	
		endc
LED_PORT	Equ	PORTB
LCD_DATA_PORT	Equ	PORTB
LED_TRIS	Equ	TRISB
LED_GREEN	Equ	0x00
LED_YELLOW	Equ	0x01

LCD_PORT	Equ	PORTA
LCD_TRIS	Equ	TRISA
LCD_RS		Equ	0x04			;LCD handshake lines
LCD_RW		Equ	0x06
LCD_E		Equ	0x07


		org	0x0000

		call	Delay100
		movlw	0x07
		movwf	CMCON			;turn comparators off (make it like a 16F84)
		goto 	Initialise

Text	addwf	PCL, f			

		retlw	' '
		retlw	' '
		retlw	'H'
		retlw	'e'
		retlw	'r'
		retlw	'b'
		retlw	'e'
		retlw	'r'
		retlw	't'
		retlw	'M'
		retlw	'u'
		retlw	'n'
		retlw	'c'
		retlw	'h'
		retlw	' '
		retlw	' '
		retlw	0x00

LCD_Init
		call 	Delay100
		
		movlw	0x28			;4bit 2 lines 5x7
		call	LCD_Cmd
			
		movlw	0x0c			;Display On
		call	LCD_Cmd

		movlw	0x06			;charactor increment on
		call	LCD_Cmd

		call	LCD_Clear

		call	LCD_Line2

		retlw 	0x00


Initialise	clrf	count
		clrf	PORTA
		clrf	PORTB
		clrf	messageCounter

SetPorts
		BANKSEL	LCD_TRIS
		CLRF	LCD_TRIS		;MAKE ALL PORTS OUTPUTS
		CLRF	LED_TRIS
		Led_On	LED_GREEN

		call	Delay100
		call    LCD_Init
	
		call 		Message
		movlw		0x02		
		call	 	LCD_Cmd




		goto 		$



Message
		clrf		messageCounter
messagego
		movf		messageCounter, w		;Set charactor index
		call		Text					;retrieve charactor
		xorlw		0x00					
		btfsc		STATUS, Z				;Check if its 0
		retlw		0x00
		call		LCD_Char
		incf		messageCounter , f
		goto		messagego


;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;LCD HD44780 Instructions
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
; Clears the screen
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
LCD_Clear
		movlw		0x01
		call		LCD_Cmd
		retlw		0x00

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
; Goes to Line2
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
LCD_Line2
		movlw		0xC0
		call		LCD_Cmd
		retlw		0x00
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;	Set the LCD CGRam address [W]
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
LCD_CGRAM_Address
		movwf		temp
		bcf			temp, 7		;Clear bit 7
		bsf			temp, 6		;Set bit 6
		movf		temp, W		;move into w
		call		LCD_Cmd		;send command
		retlw 		0x00


;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;	Shift the LCD display Left
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
LCD_ShiftDisplay_Left
		movlw		0x18
		call		LCD_Cmd		;send command
		retlw 		0x00
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;	Shift the LCD display Left
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
LCD_ShiftDisplay_Right
		movlw		0x1C
		call		LCD_Cmd		;send command
		retlw 		0x00

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;	Set the LCD Display address [W]
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
LCD_Display_Address
		movwf		temp
		bsf			temp, 7		;ensure bit 7 is set
		movf		temp, W		;move into w
		call		LCD_Cmd		;send command
		retlw 		0x00


	
		
		


;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;LCD CORE ROUTINES
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;



LCD_Cmd
		Led_On	    LED_YELLOW
	
		movwf		templcd
		swapf		templcd, w			;swap nibbles around, so we send the high nibble first on a0-a3
		andlw		0x0f				;clear LCD handshaking lines
		movwf		LCD_PORT			;set data
		movwf		LCD_DATA_PORT
		bcf			LCD_PORT,LCD_RS		;set up instruction
		call		Pulse_E				;Inform lcd data ready. Send high nibble
		movf		templcd, w			;Select lower nibble
		andlw		0x0f				;clear LCD handshaking lines
		movwf		LCD_PORT
		movwf		LCD_DATA_PORT
		bcf			LCD_PORT,LCD_RS		;Instruction
		call		Pulse_E				;inform lcd data ready. Send low nibble
		call		Delay100			;Wait until lcd ready.
		Led_Off	    LED_YELLOW
		retlw		0x00

LCD_CharA	movwf	templcd
		swapf	templcd,	w	;send upper nibble
		andlw	0x0f			;clear upper 4 bits of W
		movwf	LCD_PORT
		bsf	LCD_PORT, LCD_RS	;RS line to 1
		call	Pulse_E			;Pulse the E line high

		movf	templcd,	w	;send lower nibble
		andlw	0x0f			;clear upper 4 bits of W
		movwf	LCD_PORT
		bsf	LCD_PORT, LCD_RS	;RS line to 1
		call	Pulse_E			;Pulse the E line high
		call 	LCD_Busy
		retlw	0x00

LCD_Char	
		Led_On		LED_YELLOW
		movwf		templcd				;store charactor
		swapf		templcd, W			;swap nibbles around, so that we send high nibble first on a0-a3
		andlw		0x0f				;clear LCD handshaking lines
		movwf		LCD_PORT			;set data on pins a0-a3
		movwf	LCD_DATA_PORT
		bsf			LCD_PORT, LCD_RS	;setup to write charactor
		call		Pulse_E				;Inform lcd data ready, send high nibble
		movf		templcd, W			;Select stored charactor
		andlw		0x0F				;Clear lcd handshaking lines, leaving data on a0-a3
		movwf		LCD_PORT			;set data on pins a0-a3
		movwf	LCD_DATA_PORT
		bsf			LCD_PORT, LCD_RS	;setup to write character
		call		Pulse_E				;send data.
		call		LCD_Busy
				
		Led_Off		LED_YELLOW
		retlw		0x00
		
		


Pulse_E
		bsf			LCD_PORT, LCD_E		;make e high
		nop
		bcf			LCD_PORT,LCD_E		;e low, signals data ready
		retlw		0x00

LCD_BusyA
		
	
MakePortInputs
		banksel		LCD_TRIS
				

MakePortOutputs


Delay255	movlw	0xff		;delay 255 mS
		goto	d0
Delay100	movlw	d'100'		;delay 100mS
		goto	d0
Delay50		movlw	d'50'		;delay 50mS
		goto	d0
Delay20		movlw	d'20'		;delay 20mS
		goto	d0
Delay5		movlw	0x05		;delay 5.000 ms (4 MHz clock)
d0		movwf	count1
d1		movlw	0xC7			;delay 1mS
		movwf	counta
		movlw	0x01
		movwf	countb
Delay_0
		decfsz	counta, f
		goto	$+2
		decfsz	countb, f
		goto	Delay_0

		decfsz	count1	,f
		goto	d1
		retlw	0x00
		






;This routine downloaded from http://www.piclist.com
Convert:                        ; Takes number in NumH:NumL
                                ; Returns decimal in
                                ; TenK:Thou:Hund:Tens:Ones
        swapf   NumH, w
	iorlw	B'11110000'
        movwf   Thou
        addwf   Thou,f
        addlw   0XE2
        movwf   Hund
        addlw   0X32
        movwf   Ones

        movf    NumH,w
        andlw   0X0F
        addwf   Hund,f
        addwf   Hund,f
        addwf   Ones,f
        addlw   0XE9
        movwf   Tens
        addwf   Tens,f
        addwf   Tens,f

        swapf   NumL,w
        andlw   0X0F
        addwf   Tens,f
        addwf   Ones,f

        rlf     Tens,f
        rlf     Ones,f
        comf    Ones,f
        rlf     Ones,f

        movf    NumL,w
        andlw   0X0F
        addwf   Ones,f
        rlf     Thou,f

        movlw   0X07
        movwf   TenK

                    ; At this point, the original number is
                    ; equal to
                    ; TenK*10000+Thou*1000+Hund*100+Tens*10+Ones
                    ; if those entities are regarded as two's
                    ; complement binary.  To be precise, all of
                    ; them are negative except TenK.  Now the number
                    ; needs to be normalized, but this can all be
                    ; done with simple byte arithmetic.

        movlw   0X0A                             ; Ten
Lb1:
        addwf   Ones,f
        decf    Tens,f
        btfss   3,0
        goto   Lb1
Lb2:
        addwf   Tens,f
        decf    Hund,f
        btfss   3,0
        goto   Lb2
Lb3:
        addwf   Hund,f
        decf    Thou,f
        btfss   3,0
        goto   Lb3
Lb4:
        addwf   Thou,f
        decf    TenK,f
        btfss   3,0
        goto   Lb4

        retlw	0x00

LCD_Busy
		bsf	STATUS,	RP0		;set bank 1
		movlw	0x0f			;set Port for input
		movwf	LCD_TRIS
		bcf	STATUS,	RP0		;set bank 0
		bcf	LCD_PORT, LCD_RS	;set LCD for command mode
		bsf	LCD_PORT, LCD_RW	;setup to read busy flag
		bsf	LCD_PORT, LCD_E
		swapf	LCD_PORT, w		;read upper nibble (busy flag)
		bcf	LCD_PORT, LCD_E		
		movwf	templcd2 
		bsf	LCD_PORT, LCD_E		;dummy read of lower nibble
		bcf	LCD_PORT, LCD_E
		btfsc	templcd2, 7		;check busy flag, high = busy
		goto	LCD_Busy		;if busy check again
		bcf	LCD_PORT, LCD_RW
		bsf	STATUS,	RP0		;set bank 1
		movlw	0x00			;set Port for output
		movwf	LCD_TRIS
		bcf	STATUS,	RP0		;set bank 0
		return

		end
Last edited by HerbertMunch; 1st October 2007 at 10:28 AM.
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Old 1st October 2007, 10:38 AM   (permalink)
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Nigel Goodwin is a splendid one to beholdNigel Goodwin is a splendid one to beholdNigel Goodwin is a splendid one to beholdNigel Goodwin is a splendid one to beholdNigel Goodwin is a splendid one to beholdNigel Goodwin is a splendid one to behold
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Check my analogue tutorials (Tutorial 11), these use the LCD on PortB of a 16F876/877 - basically you just need to alter the equ at the start.
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Old 1st October 2007, 10:45 AM   (permalink)
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Thats what I have done.
The code above works fine if its on a0 -a3.
For a reason that I cant determin, it refuses to work on b0-b3!
I just dont understand it. Ive only changed a few lines, but it doesnt work.
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Old 1st October 2007, 10:58 AM   (permalink)
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Well the code above still has the LCD_PORT and LCD_TRIS set to PortA.
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Old 1st October 2007, 11:20 AM   (permalink)
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Yes it does.
As i stated before, I set the data on both port a and portB.
i,e
Code:
LCD_DATA_PORT	Equ	PORTB
LCD_PORT            Equ     PORTA


LCD_Cmd
		Led_On	    LED_YELLOW
	
		movwf		templcd
		swapf		templcd, w			;swap nibbles around, so we send the high nibble first on a0-a3
		andlw		0x0f				;clear LCD handshaking lines
		movwf		LCD_PORT			;set data
		movwf		LCD_DATA_PORT
		bcf			LCD_PORT,LCD_RS		;set up instruction
		call		Pulse_E				;Inform lcd data ready. Send high nibble
		movf		templcd, w			;Select lower nibble
		andlw		0x0f				;clear LCD handshaking lines
		movwf		LCD_PORT
		movwf		LCD_DATA_PORT
		bcf			LCD_PORT,LCD_RS		;Instruction
		call		Pulse_E				;inform lcd data ready. Send low nibble
		call		Delay100			;Wait until lcd ready.
		Led_Off	    LED_YELLOW
		retlw		0x00
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Old 1st October 2007, 11:29 AM   (permalink)
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Quote:
Originally Posted by HerbertMunch
Yes it does.
As i stated before, I set the data on both port a and portB.
What made you think you could do that?. As it is you've got part of the routines accessing PortA, and part accessing PortB.

All equates are is a text substitution, just like using 'search and replace' in a word processor.
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Old 1st October 2007, 11:44 AM   (permalink)
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I think I understand what your saying nigel, but if you look at my code youll see that the LCD control lines (R/W, R/S, E) remain unchanged. I leave them alone on port A.

The only modification I have made is to also copy the data onto portB as well as A.

And for some reason this does not work.

Please Ignore any routines with suffix A. These are just old routines.
Below is the code with all needless routines removed.

Code:
LIST	p=16F628a		;tell assembler what chip we are using
	include "P16F628a.inc"		;include the defaults for the chip
	ERRORLEVEL	0,	-302	;suppress bank selection messages
	__cONFIG	_CP_OFF &_PWRTE_OFF  & _WDT_OFF &_DATA_CP_OFF & _MCLRE_OFF & _INTOSC_OSC_NOCLKOUT &_LVP_OFF


		cblock	0x20			;start of general purpose registers
			count			;used in looping routines
			count1			;used in delay routine
			counta			;used in delay routine
			countb			;used in delay routine

			temp
			delayCountA
			delayCountB
			delayCountC
			messageCounter
			tmp1			;temporary storage
			tmp2
			templcd			;temp store for 4 bit mode
			templcd2
			
        		NumL			;Binary inputs for decimal convert routine
	        	NumH	

        		TenK			;Decimal outputs from convert routine
	        	Thou	
        		Hund	
	        	Tens	
        		Ones	
		endc
LED_PORT	Equ	PORTB
LCD_DATA_PORT	Equ	PORTB
LED_TRIS	Equ	TRISB
LED_GREEN	Equ	0x00
LED_YELLOW	Equ	0x01

LCD_PORT	Equ	PORTA
LCD_TRIS	Equ	TRISA
LCD_RS		Equ	0x04			;LCD handshake lines
LCD_RW		Equ	0x06
LCD_E		Equ	0x07


		org	0x0000

		call	Delay100
		movlw	0x07
		movwf	CMCON			;turn comparators off (make it like a 16F84)
		goto 	Initialise

Text	addwf	PCL, f			

		retlw	' '
		retlw	' '
		retlw	'H'
		retlw	'e'
		retlw	'r'
		retlw	'b'
		retlw	'e'
		retlw	'r'
		retlw	't'
		retlw	'M'
		retlw	'u'
		retlw	'n'
		retlw	'c'
		retlw	'h'
		retlw	' '
		retlw	' '
		retlw	0x00

LCD_Init
		call 	Delay100
		
		movlw	0x28			;4bit 2 lines 5x7
		call	LCD_Cmd
			
		movlw	0x0c			;Display On
		call	LCD_Cmd

		movlw	0x06			;charactor increment on
		call	LCD_Cmd

		call	LCD_Clear

		call	LCD_Line2

		retlw 	0x00


Initialise	clrf	count
		clrf	PORTA
		clrf	PORTB
		clrf	messageCounter

SetPorts
		BANKSEL	LCD_TRIS
		CLRF	LCD_TRIS		;MAKE ALL PORTS OUTPUTS
		CLRF	LED_TRIS
		Led_On	LED_GREEN

		call	Delay100
		call    LCD_Init
	
		call 		Message
		movlw		0x02		
		call	 	LCD_Cmd




		goto 		$



Message
		clrf		messageCounter
messagego
		movf		messageCounter, w		;Set charactor index
		call		Text					;retrieve charactor
		xorlw		0x00					
		btfsc		STATUS, Z				;Check if its 0
		retlw		0x00
		call		LCD_Char
		incf		messageCounter , f
		goto		messagego


;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;LCD HD44780 Instructions
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
; Clears the screen
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
LCD_Clear
		movlw		0x01
		call		LCD_Cmd
		retlw		0x00



	
		
		


;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;LCD CORE ROUTINES
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;



LCD_Cmd
		Led_On	    LED_YELLOW
	
		movwf		templcd
		swapf		templcd, w			;swap nibbles around, so we send the high nibble first on a0-a3
		andlw		0x0f				;clear LCD handshaking lines
		movwf		LCD_PORT			;set data
		movwf		LCD_DATA_PORT
		bcf			LCD_PORT,LCD_RS		;set up instruction
		call		Pulse_E				;Inform lcd data ready. Send high nibble
		movf		templcd, w			;Select lower nibble
		andlw		0x0f				;clear LCD handshaking lines
		movwf		LCD_PORT
		movwf		LCD_DATA_PORT
		bcf			LCD_PORT,LCD_RS		;Instruction
		call		Pulse_E				;inform lcd data ready. Send low nibble
		call		Delay100			;Wait until lcd ready.
		Led_Off	    LED_YELLOW
		retlw		0x00


LCD_Char	
		Led_On		LED_YELLOW
		movwf		templcd				;store charactor
		swapf		templcd, W			;swap nibbles around, so that we send high nibble first on a0-a3
		andlw		0x0f				;clear LCD handshaking lines
		movwf		LCD_PORT			;set data on pins a0-a3
		movwf	LCD_DATA_PORT
		bsf			LCD_PORT, LCD_RS	;setup to write charactor
		call		Pulse_E				;Inform lcd data ready, send high nibble
		movf		templcd, W			;Select stored charactor
		andlw		0x0F				;Clear lcd handshaking lines, leaving data on a0-a3
		movwf		LCD_PORT			;set data on pins a0-a3
		movwf	LCD_DATA_PORT
		bsf			LCD_PORT, LCD_RS	;setup to write character
		call		Pulse_E				;send data.
		call		LCD_Busy
				
		Led_Off		LED_YELLOW
		retlw		0x00
		
		


Pulse_E
		bsf			LCD_PORT, LCD_E		;make e high
		nop
		bcf			LCD_PORT,LCD_E		;e low, signals data ready
		retlw		0x00

	


Delay255	movlw	0xff		;delay 255 mS
		goto	d0
Delay100	movlw	d'100'		;delay 100mS
		goto	d0
Delay50		movlw	d'50'		;delay 50mS
		goto	d0
Delay20		movlw	d'20'		;delay 20mS
		goto	d0
Delay5		movlw	0x05		;delay 5.000 ms (4 MHz clock)
d0		movwf	count1
d1		movlw	0xC7			;delay 1mS
		movwf	counta
		movlw	0x01
		movwf	countb
Delay_0
		decfsz	counta, f
		goto	$+2
		decfsz	countb, f
		goto	Delay_0

		decfsz	count1	,f
		goto	d1
		retlw	0x00
		






;This routine downloaded from http://www.piclist.com
Convert:                        ; Takes number in NumH:NumL
                                ; Returns decimal in
                                ; TenK:Thou:Hund:Tens:Ones
        swapf   NumH, w
	iorlw	B'11110000'
        movwf   Thou
        addwf   Thou,f
        addlw   0XE2
        movwf   Hund
        addlw   0X32
        movwf   Ones

        movf    NumH,w
        andlw   0X0F
        addwf   Hund,f
        addwf   Hund,f
        addwf   Ones,f
        addlw   0XE9
        movwf   Tens
        addwf   Tens,f
        addwf   Tens,f

        swapf   NumL,w
        andlw   0X0F
        addwf   Tens,f
        addwf   Ones,f

        rlf     Tens,f
        rlf     Ones,f
        comf    Ones,f
        rlf     Ones,f

        movf    NumL,w
        andlw   0X0F
        addwf   Ones,f
        rlf     Thou,f

        movlw   0X07
        movwf   TenK

                    ; At this point, the original number is
                    ; equal to
                    ; TenK*10000+Thou*1000+Hund*100+Tens*10+Ones
                    ; if those entities are regarded as two's
                    ; complement binary.  To be precise, all of
                    ; them are negative except TenK.  Now the number
                    ; needs to be normalized, but this can all be
                    ; done with simple byte arithmetic.

        movlw   0X0A                             ; Ten
Lb1:
        addwf   Ones,f
        decf    Tens,f
        btfss   3,0
        goto   Lb1
Lb2:
        addwf   Tens,f
        decf    Hund,f
        btfss   3,0
        goto   Lb2
Lb3:
        addwf   Hund,f
        decf    Thou,f
        btfss   3,0
        goto   Lb3
Lb4:
        addwf   Thou,f
        decf    TenK,f
        btfss   3,0
        goto   Lb4

        retlw	0x00

LCD_Busy
		bsf	STATUS,	RP0		;set bank 1
		movlw	0x0f			;set Port for input
		movwf	LCD_TRIS
		bcf	STATUS,	RP0		;set bank 0
		bcf	LCD_PORT, LCD_RS	;set LCD for command mode
		bsf	LCD_PORT, LCD_RW	;setup to read busy flag
		bsf	LCD_PORT, LCD_E
		swapf	LCD_PORT, w		;read upper nibble (busy flag)
		bcf	LCD_PORT, LCD_E		
		movwf	templcd2 
		bsf	LCD_PORT, LCD_E		;dummy read of lower nibble
		bcf	LCD_PORT, LCD_E
		btfsc	templcd2, 7		;check busy flag, high = busy
		goto	LCD_Busy		;if busy check again
		bcf	LCD_PORT, LCD_RW
		bsf	STATUS,	RP0		;set bank 1
		movlw	0x00			;set Port for output
		movwf	LCD_TRIS
		bcf	STATUS,	RP0		;set bank 0
		return

		end
Last edited by HerbertMunch; 1st October 2007 at 11:46 AM.
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Old 1st October 2007, 11:52 AM   (permalink)
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Why would you want to only move part of the LCD to a different port?.

The routines were written to use a single port, and (as you've perhaps found out?) may well require modification to work across different ports.
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Old 1st October 2007, 04:09 PM   (permalink)
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Quote:
Why would you want to only move part of the LCD to a different port?.
to be able to use ad conversion
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Old 1st October 2007, 04:10 PM   (permalink)
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Quote:
Originally Posted by Nigel Goodwin
may well require modification to work across different ports.
Yeah thats why im asking the question! I have modified it as far as I can, but still no luck!

As far as I can tell, it will require no further modification, as Im still using ports 0-3 for data.
Last edited by HerbertMunch; 1st October 2007 at 04:14 PM.
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Old 1st October 2007, 04:32 PM   (permalink)
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hi herbert,

Post the full code [yours] and I'll run in thru my simulator.
Add any necessary comments
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Old 1st October 2007, 04:42 PM   (permalink)
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Ok thanks mate.
Ill clean it up, and resubmit.
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Old 1st October 2007, 05:06 PM   (permalink)
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Quote:
Originally Posted by HerbertMunch
Ok thanks mate.
Ill clean it up, and resubmit.
Hi,
Where did you get the original code from,, point me to it.
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Old 1st October 2007, 05:14 PM   (permalink)
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It’s an amalgamation of Nigels LCD tutorials, slightly modified by me.
Found Here.

Ive taken out the read busy flag code though.

When I connect it up to A0-A3, all is well.
When I connect it up to B0-B3 it doesnt even initiliase the LCD!

I feel like im just bagging my head against a music festival toilette! I just cant work out why this doesnt work.
All the pins (B) are functioning properly as outputs. I have pulsed and scoped all of them.
Last edited by HerbertMunch; 1st October 2007 at 05:27 PM.
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Old 1st October 2007, 10:31 PM   (permalink)
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Quote:
Originally Posted by HerbertMunch
to be able to use ad conversion
Well move the entire port, not just part of it!.
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