LCDout and large filesize 18F452 -> paging problem?
Howdy,
LCD is in portD (data=D.0-D.3,RS=D.4,En=D.5)
TRISD = %01000000 (D.6 is input)
LCDout interferes pin D.7 as program size grows
PortD.7 = 1 won't make pin high...
pulsout portD.7,10000 still works... cannot figure it out.. o:-)
If I decrease code size, the problem disappears...
Has anyone faced same kinda problems?
thnx adv.
m.
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Post the code...
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Code is basicly like this:
DEFINE LCD_BITS 4
DEFINE LCD_DREG PORTD
DEFINE LCD_DBIT 0
DEFINE LCD_RSREG PORTD
DEFINE LCD_RSBIT 4
DEFINE LCD_EREG PORTD
DEFINE LCD_EBIT 5
TRISD = %01000000
LED VAR portD.7
...
--->8---(klipeti-klipeti)--->8--- (lots of stuff)
...
Lcdsub:
lcdout $FE,2,"hello"
lcdout $FE,C0,"world"
return
...
main:
LED=1 ' This should illuminate the led?
gosub Lcdsub
pause 500
LED=0
pause 500
goto Main
So, if I replace LED=1 with pulsout portD.7,65530 it will blink..
Otherwise it wont.. BUT..
If I remove gosubs away, LED=1 will work and it LED will blink..
Originally Posted by skimask
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It's this that makes it suspicious.
And which version of PBP are you using?
Last edited by skimask; - 24th January 2008 at 16:02.
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> It's this that makes it suspicious.
yep, I know.. the code is 500 lines...
I just tried to save some bandwidth.. o:-)
> And which version of PBP are you using?[/QUOTE]
pbpro v:2.50a and uCodeStudio+ v:3.005
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Ok, how about this code, and ONLY this code:
Code:DEFINE LCD_BITS 4 DEFINE LCD_DREG PORTD DEFINE LCD_DBIT 0 DEFINE LCD_RSREG PORTD DEFINE LCD_RSBIT 4 DEFINE LCD_EREG PORTD DEFINE LCD_EBIT 5 TRISD = %10000000 LED VAR portD.7 Lcdsub: lcdout $FE,2,"hello" : lcdout $FE,C0,"world" : return main: LED=1 : gosub Lcdsub : pause 500 : LED=0 : pause 500 : goto Main END
Last edited by skimask; - 24th January 2008 at 18:09.
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Looong IF-THEN-ELSE structures?
> Ok, how about this code, and ONLY this code:
Well, I dunno.. BUT I got another question..
What would happen if IF-THEN-ELSE overlaps from memory-page to another? Is it allowed? Is pbp-compiler capable of handle veeeeery loooooong IF-THEN-ELSE structures (like 200lines long?) including gosubs from page to page? If not-should I get a warning? o:-)
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I don't have any problem with what you're talking about, with 2.50a anyways. But quite frankly, I just avoid it altogether by just making the 'middle' of the If/Then another routine.
I've had some programs (one in particular), over 4300 lines long (and that's compacted with a lot of colons like I do often, uncompacted, figure roughly 13,000+ lines). Never had a problem with the amount of code inside of an If/Then, Select Case, While/Wend, or otherwise.
You tend to forget things like RETURN after a GOSUB, or maybe you RETURN from somewhere that you had GOTO'd instead of GOSUB'd. Keep that in mind. I just fixed a buried GOSUB (one of the drawbacks of 'compacting' source code) that would only show up after the loop went thru itself 32 times and ended up causing a stack overflow which killed my entire OS on the one project. I've been fighting it for over 6 months now.
And paging really isn't so much of an issue, moreso with 18F series PICs, and even moreso with PBP for the last few years.
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> You tend to forget things like RETURN after a GOSUB..
Yep, gosubs and if-then-else-endif structures are like women-
one has to be veeery careful with them.. o:-)
I downsized the code a little bit - any comments?
It works if naytto is low,
If naytto is high then portD.7 wont go high (except pulsout-command)
Last edited by mara; - 24th January 2008 at 21:14. Reason: pdf updated
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Yes, does the code in Post #6 work?
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> Yes, does the code in Post #6 work?
Well, did ya mean reversing direction-bit of portD.7?
I don't think it would resolve the problem-
in this case the problem is deepper-I think it is in compiler...
The code works ok, only the LCDout routine is causing problems..
(=jamming portD.7)
m.
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Ok, typo on my part...
TRISD = %10000000 should have been
TRISD = $40
Did it work or not?
Looking at your program as a whole, I think the problem is that the LED is actually coming on, but that it flickers too fast for you to see it. With the pulsout, you are seeing a .13 second pulse, if your code says something to the effect of:
LED1 = 1
LED1 = 0
then you probably won't see it come on at all...unless you got really super special eyes.
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Be careful with 18Fs.. when you write to a PORT you should use LATx instead of PORTx. If you write to adjacent bits, you should write to a shadow register first, then copy it to the whole port to avoid the Read-Modify-Write behaviour.
I would tend to change the LCDOUT statement... reading the Magn bit (from PORTD.7), save the result to a Temp variable then after show the result. When writing to Magn, you use LATD.7.
Steve
It's not a bug, it's a random feature.
There's no problem, only learning opportunities.
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I've never used, or had to use, LATD.x on the 18F's.
But if you say it takes care of some of the R-M-W issues, then it must be true.
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> I've never used, or had to use, LATD.x on the 18F's.
> But if you say it takes care of some of the R-M-W issues,
> then it must be true.
This might be worth deepper inspection..
I'm sorry I didn't identify the problem clearly-basicly LCDout works just fine. LCD-display can be used only for testing purposes cause it's so damn slooooow.. o:-) That's why all lcd-routines are normally bypassed by "naytto" input signal. Only problem is that if I want to use LCDout for testing, it will shut down (low) portD.7 output (MAGN) as well.. There cannot be hardware problem cause in next line I put pulsout portD.7,65530 command for testing purposes and it will flash Led in portD.7 but I cannot understand why in previous line command portD.7=1 (Magn=1) will NOT illuminate the same led.. (see line marked in RED=near lines 145 and 182)
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as i said, you want to use LATD instead of PORTD. Pulsout also do more than a single PORT/LAT=x. If my memory serves me well it set the TRIS.. then do what it has to do. Hence wasting a few instruction cycle before and after... why the R-M-W behaviour don't happen.. or is reduced to a minimum.
Steve
It's not a bug, it's a random feature.
There's no problem, only learning opportunities.
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> as i said, you want to use LATD instead of PORTD.
Ok, u do have a point and that must be the issue here.. BUT..
could it be so that the LCDout-command is causing this RMW behaviour and not the other way around?
I mean without LCDout everything works fine.. o:-)
what can I do about that build-in LCDout-command?
I don't have time and energy to write my own LCDout-command..
o:-)
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> as i said, you want to use LATD instead of PORTD.
Ok, Now i know it is about RMW. As I put "pause 5000" right after portD.7=1 command, the led in portD.7 will light for 5seconds.
There ain't any other solution than find another port for output-like portB.1?
Last edited by mara; - 24th January 2008 at 22:28.
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Ok, now it works: instead of portD.7=1 I write:
latd.7=0
latd.7=1
and now portD.7 will stay high even if LCDout is used..
BUT.. why do I have to do it that way? o:-)
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