;if portb.0 <> tmp then
movf TMP,W
subwf PORTB.0,W '**********
btfsc STATUS, Z
goto ENDIF1
;portb.0 = tmp
bcf PORTB,0
movf TMP,F
btfss STATUS,Z
bsf PORTB,0
;end if
ENDIF1
The assembler was not happy with PORT.0 on the subwf line
Also, I only discovered this because the following line-
if portb.0 <> portb.4 then portb.0 = portb.4
would always clear portb.0 before setting it to portb.4 even if it was already on and was supposed to be set on, which really had me confused for quite a while.
resulting code:
I'm sure it's here somewhere, but I couldn't find the edit button to fix the typos in my post. so….
the line - "The assembler was not happy with PORT.0 on the subwf line"
should have read The MPASM v5.49 assembler was not happy with PORTB.0 on the subwf line
If you would like to refer to this comment somewhere else in this project, copy and paste the following link:
Anonymous
-
2013-04-15
Hi ,
try this
varA=portb.0
if varA <> tmp then portb.0 =tmp
and your next piece of code could be written like this:
varA=portb.0
varB=portb.4
if varA <> varB then portb.0 =varB
If you would like to refer to this comment somewhere else in this project, copy and paste the following link:
It appears you are comparing a bit to a byte and
it appears the compiler is treating portb.0 as a byte since it's being compared to a byte variable tmp.
PORTB.0 isn't a register the compiler recognizes so it kicks it out.
Since it appears that you are testing if the the variable temp is empty,
Try it this way:
If tmp = 0 then
portb.0 = 0
else
portb.0 = 1
endif
Or
declare tmp as a bit variable and then see if it fixes the problem.
If you would like to refer to this comment somewhere else in this project, copy and paste the following link:
I believe you did find a bug in the command line: if portb.0 <> portb.4 then portb.0 = portb.4.
I don't believe it works properly at all.
I believe the
btfss STATUS,Z
should be replaced by
btfsc STATUS,Z
Here is my summary, in case someone can find an error in my conclusion, I think this minor change will fix the bug you found.
************************************* Current Execution with btfss STATUS,Z ***********************************
----- portb.0 = 0, portb.4 = 0 ---------
;if portb.0 <> portb.4 then portb.0 = portb.4
clrw ;w = 0
btfsc PORTB,0 ;clear so skip next line
xorlw 255
btfsc PORTB,4 ;clear so skip next line
xorlw 255
btfss STATUS,Z ;Z = 1 so skip next line
goto ENDIF1
bcf PORTB,0 ;portb.0 = 0
btfsc PORTB,4 ;portb.4 = 0 so skip next line
bsf PORTB,0
ENDIF1
Result: portb.0 = 0, portb.4 = 0 Issue: None
------- portb.0 = 1, portb.4 = 1 -------
;if portb.0 <> portb.4 then portb.0 = portb.4
clrw ;w = 0
btfsc PORTB,0 ;not clear so next line
xorlw 255 ;w = 255
btfsc PORTB,4 ;not clear so next line
xorlw 255 ;w = 0
btfss STATUS,Z ;Z = 1 so skip next line
goto ENDIF1
bcf PORTB,0 ;clear portb.0
btfsc PORTB,4 ;not clear so next line
bsf PORTB,0 ;set portb.0
ENDIF1
Result: portb.0 = 1, portb,4 = 1 Issue: portb.0 glitches 1-0-1 for one clock cycle.
----- portb.0 = 0, portb.4 = 1 ----------
;if portb.0 <> portb.4 then portb.0 = portb.4
clrw ;w = 0
btfsc PORTB,0 ;clear skip next line
xorlw 255
btfsc PORTB,4 ;not clear so next line
xorlw 255 ;w = 255
btfss STATUS,Z ;Z = 0 so next line
goto ENDIF1
bcf PORTB,0
btfsc PORTB,4
bsf PORTB,0
ENDIF1
Result: portb.0 = 0, portb.4 = 1 Issue: Since they are unequal, portb.0 should be set to one to match portb.4
----- portb.0 = 1, portb.4 = 0 ---------
;if portb.0 <> portb.4 then portb.0 = portb.4
clrw ;w = 0
btfsc PORTB,0 ;not clear so next line
xorlw 255 ;w = 255
btfsc PORTB,4 ;clear so skip next line
xorlw 255
btfss STATUS,Z ;Z = 0 so next line
goto ENDIF1
bcf PORTB,0
btfsc PORTB,4
bsf PORTB,0
ENDIF1
Result: portb.0 = 1, portb.4 = 0 Issue: Since they are unequal, portb.0 should be set to zero.
************************************* Fix: Replace btfss STATUS,Z with btfsc STATUS,Z ***********************************
----- portb.0 = 0, portb.4 = 0 ---------
;if portb.0 <> portb.4 then portb.0 = portb.4
clrw ;w = 0
btfsc PORTB,0 ;clear so skip next line
xorlw 255
btfsc PORTB,4 ;clear so skip next line
xorlw 255
btfsc STATUS,Z ;Z = 1 so next line
goto ENDIF1
bcf PORTB,0
btfsc PORTB,4
bsf PORTB,0
ENDIF1
Result: portb.0 = 0, portb.4 = 0 Issue: None
------- portb.0 = 1, portb.4 = 1 -------
;if portb.0 <> portb.4 then portb.0 = portb.4
clrw ;w = 0
btfsc PORTB,0 ;not clear so next line
xorlw 255 ;w = 255
btfsc PORTB,4 ;not clear so next line
xorlw 255 ;w = 0
btfsc STATUS,Z ;Z = 1 so next line
goto ENDIF1
bcf PORTB,0
btfsc PORTB,4
bsf PORTB,0
ENDIF1
Result: portb.0 = 1, portb,4 = 1 Issue: none
----- portb.0 = 0, portb.4 = 1 ----------
;if portb.0 <> portb.4 then portb.0 = portb.4
clrw ;w = 0
btfsc PORTB,0 ;clear skip next line
xorlw 255
btfsc PORTB,4 ;not clear so next line
xorlw 255 ;w = 255
btfsc STATUS,Z ;Z = 0 so skip next line
goto ENDIF1
bcf PORTB,0 ;portb.0 = 0
btfsc PORTB,4 ;portb.4 = 1 so next line
bsf PORTB,0 ;portb.0 = 1
ENDIF1
Result: portb.0 = 1, portb.4 = 1 Issue: none
----- portb.0 = 1, portb.4 = 0 ---------
;if portb.0 <> portb.4 then portb.0 = portb.4
clrw ;w = 0
btfsc PORTB,0 ;not clear so next line
xorlw 255 ;w = 255
btfsc PORTB,4 ;clear so skip next line
xorlw 255
btfsc STATUS,Z ;Z = 0 so skip next line
goto ENDIF1
bcf PORTB,0 ;portb.0 = 0
btfsc PORTB,4 ;portb.4 = 1 so skip next line
bsf PORTB,0
ENDIF1
Result: portb.0 = 0, portb.4 = 0 Issue: none
If you would like to refer to this comment somewhere else in this project, copy and paste the following link:
Does anybody know where this source code is within GCB?
I'd like to read it over to understand where this is generated.
I also sent an email to Hugh pointing out this potential bug for his expert view on this.
If you would like to refer to this comment somewhere else in this project, copy and paste the following link:
I've made a few changes to GCBASIC that should fix these problems. Please download the update from http://gcbasic.sourceforge.net/update.html and let me know if that helps!
The problem was in the CompileConditions subroutine, which is inside gcbasic.bas.
If you would like to refer to this comment somewhere else in this project, copy and paste the following link:
The following code
compiled as
;if portb.0 <> tmp then movf TMP,W subwf PORTB.0,W '********** btfsc STATUS, Z goto ENDIF1 ;portb.0 = tmp bcf PORTB,0 movf TMP,F btfss STATUS,Z bsf PORTB,0 ;end if ENDIF1The assembler was not happy with PORT.0 on the subwf line
Also, I only discovered this because the following line-
would always clear portb.0 before setting it to portb.4 even if it was already on and was supposed to be set on, which really had me confused for quite a while.
resulting code:
;if portb.0 <> portb.4 then portb.0 = portb.4 clrw btfsc PORTB,0 xorlw 255 btfsc PORTB,4 xorlw 255 btfss STATUS,Z goto ENDIF1 bcf PORTB,0 btfsc PORTB,4 bsf PORTB,0 ENDIF1I'm sure it's here somewhere, but I couldn't find the edit button to fix the typos in my post. so….
the line - "The assembler was not happy with PORT.0 on the subwf line"
should have read The MPASM v5.49 assembler was not happy with PORTB.0 on the subwf line
Hi ,
try this
and your next piece of code could be written like this:
It appears you are comparing a bit to a byte and
it appears the compiler is treating portb.0 as a byte since it's being compared to a byte variable tmp.
PORTB.0 isn't a register the compiler recognizes so it kicks it out.
Since it appears that you are testing if the the variable temp is empty,
Try it this way:
If tmp = 0 then
portb.0 = 0
else
portb.0 = 1
endif
Or
declare tmp as a bit variable and then see if it fixes the problem.
Well, yes, both methods will probably work, and I did what I wanted with even a third method, but…
I was just reporting a compiler bug that I thought should be fixed.
Also, apologies for posting in the wrong section of the forum, I see now this is the graphical section. Oops.
I believe you did find a bug in the command line: if portb.0 <> portb.4 then portb.0 = portb.4.
I don't believe it works properly at all.
I believe the
btfss STATUS,Z
should be replaced by
btfsc STATUS,Z
Here is my summary, in case someone can find an error in my conclusion, I think this minor change will fix the bug you found.
************************************* Current Execution with btfss STATUS,Z ***********************************
----- portb.0 = 0, portb.4 = 0 ---------
;if portb.0 <> portb.4 then portb.0 = portb.4
clrw ;w = 0
btfsc PORTB,0 ;clear so skip next line
xorlw 255
btfsc PORTB,4 ;clear so skip next line
xorlw 255
btfss STATUS,Z ;Z = 1 so skip next line
goto ENDIF1
bcf PORTB,0 ;portb.0 = 0
btfsc PORTB,4 ;portb.4 = 0 so skip next line
bsf PORTB,0
ENDIF1
Result: portb.0 = 0, portb.4 = 0
Issue: None
------- portb.0 = 1, portb.4 = 1 -------
;if portb.0 <> portb.4 then portb.0 = portb.4
clrw ;w = 0
btfsc PORTB,0 ;not clear so next line
xorlw 255 ;w = 255
btfsc PORTB,4 ;not clear so next line
xorlw 255 ;w = 0
btfss STATUS,Z ;Z = 1 so skip next line
goto ENDIF1
bcf PORTB,0 ;clear portb.0
btfsc PORTB,4 ;not clear so next line
bsf PORTB,0 ;set portb.0
ENDIF1
Result: portb.0 = 1, portb,4 = 1
Issue: portb.0 glitches 1-0-1 for one clock cycle.
----- portb.0 = 0, portb.4 = 1 ----------
;if portb.0 <> portb.4 then portb.0 = portb.4
clrw ;w = 0
btfsc PORTB,0 ;clear skip next line
xorlw 255
btfsc PORTB,4 ;not clear so next line
xorlw 255 ;w = 255
btfss STATUS,Z ;Z = 0 so next line
goto ENDIF1
bcf PORTB,0
btfsc PORTB,4
bsf PORTB,0
ENDIF1
Result: portb.0 = 0, portb.4 = 1
Issue: Since they are unequal, portb.0 should be set to one to match portb.4
----- portb.0 = 1, portb.4 = 0 ---------
;if portb.0 <> portb.4 then portb.0 = portb.4
clrw ;w = 0
btfsc PORTB,0 ;not clear so next line
xorlw 255 ;w = 255
btfsc PORTB,4 ;clear so skip next line
xorlw 255
btfss STATUS,Z ;Z = 0 so next line
goto ENDIF1
bcf PORTB,0
btfsc PORTB,4
bsf PORTB,0
ENDIF1
Result: portb.0 = 1, portb.4 = 0
Issue: Since they are unequal, portb.0 should be set to zero.
************************************* Fix: Replace btfss STATUS,Z with btfsc STATUS,Z ***********************************
----- portb.0 = 0, portb.4 = 0 ---------
;if portb.0 <> portb.4 then portb.0 = portb.4
clrw ;w = 0
btfsc PORTB,0 ;clear so skip next line
xorlw 255
btfsc PORTB,4 ;clear so skip next line
xorlw 255
btfsc STATUS,Z ;Z = 1 so next line
goto ENDIF1
bcf PORTB,0
btfsc PORTB,4
bsf PORTB,0
ENDIF1
Result: portb.0 = 0, portb.4 = 0
Issue: None
------- portb.0 = 1, portb.4 = 1 -------
;if portb.0 <> portb.4 then portb.0 = portb.4
clrw ;w = 0
btfsc PORTB,0 ;not clear so next line
xorlw 255 ;w = 255
btfsc PORTB,4 ;not clear so next line
xorlw 255 ;w = 0
btfsc STATUS,Z ;Z = 1 so next line
goto ENDIF1
bcf PORTB,0
btfsc PORTB,4
bsf PORTB,0
ENDIF1
Result: portb.0 = 1, portb,4 = 1
Issue: none
----- portb.0 = 0, portb.4 = 1 ----------
;if portb.0 <> portb.4 then portb.0 = portb.4
clrw ;w = 0
btfsc PORTB,0 ;clear skip next line
xorlw 255
btfsc PORTB,4 ;not clear so next line
xorlw 255 ;w = 255
btfsc STATUS,Z ;Z = 0 so skip next line
goto ENDIF1
bcf PORTB,0 ;portb.0 = 0
btfsc PORTB,4 ;portb.4 = 1 so next line
bsf PORTB,0 ;portb.0 = 1
ENDIF1
Result: portb.0 = 1, portb.4 = 1
Issue: none
----- portb.0 = 1, portb.4 = 0 ---------
;if portb.0 <> portb.4 then portb.0 = portb.4
clrw ;w = 0
btfsc PORTB,0 ;not clear so next line
xorlw 255 ;w = 255
btfsc PORTB,4 ;clear so skip next line
xorlw 255
btfsc STATUS,Z ;Z = 0 so skip next line
goto ENDIF1
bcf PORTB,0 ;portb.0 = 0
btfsc PORTB,4 ;portb.4 = 1 so skip next line
bsf PORTB,0
ENDIF1
Result: portb.0 = 0, portb.4 = 0
Issue: none
Does anybody know where this source code is within GCB?
I'd like to read it over to understand where this is generated.
I also sent an email to Hugh pointing out this potential bug for his expert view on this.
I've made a few changes to GCBASIC that should fix these problems. Please download the update from http://gcbasic.sourceforge.net/update.html and let me know if that helps!
The problem was in the CompileConditions subroutine, which is inside gcbasic.bas.
When i try to dezip update.zip i got always HEADER CORRUPTED.
The zip file size on disk is 3,45 MB (3.620.864 byte)
PS: GCB i wordefull program :)
Sorry I took so long to get back. The new update.zip change works for me. Thanks much.