anybody familier with nigels tutorials?

[kutalinelucas]

hi

i followed nigel goodwins tutorial on lcd display which was great worked perfectly well on a breadboard for part of my project.
i have now put it on a pcb and to make the tracks more straight forward, i have changed the ports of the 4 data lines from ra3 -> ra0, to rb7 -> rb4, and now the lcd just shows nosensical rubbish.
could somebody please help me with a way i could somehow use the new data ports in the lcd_cmd and lcd_char routines?

thanks

 

[Nigel Goodwin]

The routines are specifically designed to work on a single port, trying to use two separate ports will mean altering the source code accordingly - and it was never designed to work that way.

 

[kutalinelucas]

no its all on the same port, i just used the upper nibble instead. like in your hardware changes page, i used port b because i am using a 16f876a, but used 7-4 for the data lines, then changed the r/w lines etc in the equates

 

[Nigel Goodwin]

You would still need to rewrite the routines, as they shuffle the data about quite a lot, in order to make it work, easier to rewire the conenctions.

 

[kutalinelucas]

thats gunna be a nightmare, but if thats all i can do!!
cheers.

 

[futz]

thats gunna be a nightmare, but if thats all i can do!!
cheers.

It's not so bad if you understand what the code is doing. Simply add/modify some lines to shuffle the bits to where they're needed before sending them out. Everything else stays the same. I've done it multiple times on different boards recently.

 

[Pommie]

It's really not difficult and definitely easier that redoing a PCB.

Try,

; command set routine
LCD_Cmd		movwf	templcd			;send upper nibble
		andlw	0x0f0			;clear lower 4 bits of W
		movwf	LCD_PORT
		bcf	LCD_PORT, LCD_RS	;RS line to 0
		call	Pulse_e			;Pulse the E line high

		swapf	templcd,	w	;send lower nibble
		andlw	0x0f0			;clear lower 4 bits of W
		movwf	LCD_PORT
		bcf	LCD_PORT, LCD_RS	;RS line to 0
		call	Pulse_e			;Pulse the E line high
		call 	Delay5
		retlw	0x00

LCD_CharD	addlw	0x30
LCD_Char	movwf	templcd			;send upper nibble
		andlw	0x0f0			;clear lower 4 bits of W
		movwf	LCD_PORT
		bsf	LCD_PORT, LCD_RS	;RS line to 1
		call	Pulse_e			;Pulse the E line high

		swapf	templcd,	w	;send lower nibble
		andlw	0x0f0			;clear lower 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 	Delay5
		retlw	0x00

Mike.

 

[kutalinelucas]

yeah i tried doing that, but didnt wrok. ah well ive ordered another pcb now.
cheers tho

 

[Pommie]

You had something else wrong then.

Mike.

 

[kutalinelucas]

you right, thank you so much. in the end it was just a bit of dogy soldering grounding one of the data lines