Stupid question about LCDOUT

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  1. - 6th October 2008, 20:45 #1
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    Quote Originally Posted by Acetronics View Post
    Hi,
    Did you notice the reversed pinout numbering ??? ... from right to left.
    Yes, I have the datasheet for the displays since I used them in aother project (connetced to the parport of a computer)
  2. - 6th October 2008, 22:01 #2
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    Quote Originally Posted by Glenn View Post
    Yes, I have the datasheet for the displays since I used them in aother project (connetced to the parport of a computer)
    Using one of those 'solderless breadboards' for the project?
    Double check those connections!!! They might be hooked up right, but are they making contact...
  3. - 6th October 2008, 22:08 #3
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    Quote Originally Posted by skimask View Post
    Using one of those 'solderless breadboards' for the project?
    Double check those connections!!! They might be hooked up right, but are they making contact...
    Yes I do, actually a new one I never used before since the other one is used for my servotests

    I measured the Vss and Vdd on the display to see that it get power, also that it get some power at Vo, but none of the other connections, but maybe I should..
  4. - 6th October 2008, 22:15 #4
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    Quote Originally Posted by Glenn View Post
    Yes I do, actually a new one I never used before since the other one is used for my servotests
    I measured the Vss and Vdd on the display to see that it get power, also that it get some power at Vo, but none of the other connections, but maybe I should..
    Right up there with the heartbeat LED, I usually put a 'blink all pins at x frequency' subroutine in there to do nothing but pulse all the pins at a known rate. Hit 'em with the logic probe or the 'scope and those questions go out the window...
    Solderless breadboards-These days, my older breadboards are usually the first suspect...
  5. - 6th October 2008, 22:32 #5
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    Quote Originally Posted by skimask View Post
    Right up there with the heartbeat LED, I usually put a 'blink all pins at x frequency' subroutine in there to do nothing but pulse all the pins at a known rate. Hit 'em with the logic probe or the 'scope and those questions go out the window...
    Solderless breadboards-These days, my older breadboards are usually the first suspect...
    I guess I can try to move the whole project to another part of the breadboard or another breadboard to test.. or trying to find the probs for the scope

    Anyway, this is waht it looks like now.. yea, I know its not a school example of how it should be done but it should work.

    http://safir.amigaos.se/bildgalleri/...0-halfsize.jpg
  6. - 6th October 2008, 22:42 #6
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    A few questions...
    Why the double-pullup resistor on RA4? Same on MCLR?
    Pin 9 on the PIC should go to pin 6 on the LCD...
    Almost looks like the LCD needs to be jammed in there a bit farther...
    Also, you really need more decoupling cap's... a couple across Vdd/Vss on both the PIC and the LCD (especially the LCD in this case) wouldn't hurt.
    Ok, I missed the part where you said you swapped over to an 'F84A.
    Those 1st 3 solder joints on the LCD don't look that good either, could be the lighting though...
    Last edited by skimask; - 6th October 2008 at 22:48.
  7. - 6th October 2008, 22:57 #7
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    I may be full of you know what...
    But I think the LCD is wired backwards. I do not have the data sheet for that one, but isn't pin 14 over by the mounting hole?
    Dave
    Always wear safety glasses while programming.
  8. - 7th October 2008, 00:11 #8
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    Quote Originally Posted by skimask View Post
    A few questions...
    Why the double-pullup resistor on RA4? Same on MCLR?
    Since I have alot of 10K resistors handy and didnt want to search for 4K7 in my big pile of resistors I used two 10K in parallel to get 5K ..and since its only a pullup its not very critical anyway.

    Pin 9 on the PIC should go to pin 6 on the LCD...
    Almost looks like the LCD needs to be jammed in there a bit farther...
    The pinstrip I used have pretty long (and very thin) pins so its no problem.

    Also, you really need more decoupling cap's... a couple across Vdd/Vss on both the PIC and the LCD (especially the LCD in this case) wouldn't hurt.
    You mean closer ? Well, I guess I could do that just to get that possibility out of the way, but I dont think it should be any problem, I use a very clean powersource and have one cap on the breadboard over Vss and Vdd.

    Ok, I missed the part where you said you swapped over to an 'F84A.
    Those 1st 3 solder joints on the LCD don't look that good either, could be the lighting though...
    The leftmost ones ? its actually flux that went white when I pressed the testpins from my multimeter to see if I really got some power to the LCD ..So no problem there, but I admit that the solderings on the ICSP-connector looks like crap ..I just made a cable between the Pickit2 and a pinstrip very quickly since I was tired of connecting and disconnecting the pickit2 all the time.
  9. - 6th October 2008, 22:06 #9
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    Ok, no I changed the pic to a 16F84A, and connetced a Xtal and two caps, still doesnt work

    Very strange.

    Now I test with:

    Code:
    @ device HS_OSC,WDT_OFF,PROTECT_OFF
DEFINE OSC 4	' Lets work at 4MHz

DEFINE LCD_DREG	PORTB		
DEFINE LCD_DBIT	4				
DEFINE LCD_RSREG	PORTB	
DEFINE LCD_RSBIT	1			
DEFINE LCD_EREG	PORTB		
DEFINE LCD_EBIT	0				
DEFINE LCD_BITS	4				
DEFINE LCD_LINES 2			
DEFINE LCD_COMMANDUS	2000	
DEFINE LCD_DATAUS	50


pause 500 ' grace time for the LCD to initialize.

main:
	LCDOUT $FE, 1, "Hello world" ' Clear display and show text
	high portb.0	' Turn the LED on.
	pause 1000	' Wait 1s
	low portb.0	' Turn the LED off.
	pause 1000	' Wait 1s
	goto main	' Go back
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