cannot find the reason for such a strange behavior

[richard]

no problem alberto glad to see you got the issues resolved , it always serves as another good example of why code snippets for debugging are a pointless exercise.
snippets are fine to discuss or explain methodology but that's about all.

it comes from having had several trouble in the past trying to tranfer the value "1" from a byte variable into a bit variable

if you can find the troublesome code i'd like to have a look at it with the view to seeing why it fails

[Alberto]

if you can find the troublesome code i'd like to have a look at it with the view to seeing why it fails

Door_Lock var PortB.4
DmyFlg var bit
Report var byte[8]


Report[2] = !Door_Lock + 48 ' (didn't work! can't remember if it fails with True or false)

The work around was

DmyFlg = Door_Lock
DmyFlg = !DmyFlg
Report[2] = DmyFlg + 48

Sorry, not exactly as I mentioned in my previous post! I should say "bit into byte"

Alberto

[richard]

The work around was

DmyFlg = Door_Lock
DmyFlg = !DmyFlg
Report[2] = DmyFlg + 48

I'M not sure you solution is correct

I did a few experiments as follows and conclude that,

if you invert a bit var (or bit alias) wether logical or bitwise only bit 0 in the result is valid , I you go on to use the result mathematically then all the other bits need to be masked off

for a correct calculation



D_Lck !D_Lck ~D_Lck D_Flg !D_Flg ~D_Flg R+!L R+~L R+!F R+~F
WRONG
0 65535 65535 0 65535 65535 47 47 47 47
CORRECT
0 255 65535 0 65535 65535 49 49 49 49
WRONG
1 65280 65534 1 65280 65534 48 46 48 46
CORRECT
1 0 65534 1 65280 65534 48 48 48 48
WRONG
0 65535 65535 0 65535 65535 47 47 47 47
CORRECT
0 255 65535 0 65535 65535 49 49 49 49

   TRISC = %11101111        ' set PORTC I/O
 

 D_Lck var Portc.4
 D_Flg var bit
 Report var byte[4]
 
 
    DEFINE DEBUG_REG PORTA
    DEFINE DEBUG_BIT 0      ;  if not used for pwr  
    DEFINE DEBUG_BAUD 9600
    DEFINE DEBUG_MODE 0     
    pause 2000
    Debug "Start",13 ,10      
 
 Debug 13 ,10 ,"D_Lck",9 ,"!D_Lck",9, "~D_Lck",9, "D_Flg",9, "!D_Flg",9, "~D_Flg" ,9, "R+!L" ,9, "R+~L" ,9, "R+!F" ,9, "R+~F"
main:
 PORTC.4=!PORTC.4
 D_Flg=D_Lck 
 Debug 13 ,10 ,"WRONG"
 Report[0] = !D_Lck + 48 
 Report[1] = ~D_Lck + 48 
 Report[2] = !D_Flg + 48 
 Report[3] = ~D_Flg + 48 
 Debug 13 ,10 ,#D_Lck,9 , #!D_Lck,9, #~D_Lck ,9, #  D_Flg ,9,  #!D_Flg, 9,# ~ D_Flg ,9,# Report[0] ,9,# Report[1] ,9,# Report[2] ,9,# Report[3]
 Debug 13 ,10 ,"CORRECT"
 Report[0] = (!D_Lck&1) + 48 
 Report[1] = (~D_Lck&1) + 48 
 Report[2] = (!D_Flg&1) + 48 
 Report[3] = (~D_Flg&1) + 48 
 Debug 13 ,10 ,#D_Lck,9 , #!D_Lck,9, #~D_Lck ,9, #  D_Flg ,9,  #!D_Flg, 9,# ~ D_Flg ,9,# Report[0] ,9,# Report[1] ,9,# Report[2] ,9,# Report[3]
  
 
 
 
  pause 1000
 
  goto main

[Alberto]

Today I have finaly found the time to implement the corrections to my code!

I have corrected the number of bytes int the array Pulse from 75 to 80. Next I have changed the following two lines of code:

DMY = W0//256
Pulse[75] = (255 - DMY)

with the simple form suggested by Richard

Pulse[75] = ~W0

Compiled (22Kb of code) and updated the mcu. Power up and checked the packet transmitted via esp NOOOO! CRC is still txed as 253 all the time!

I did change the code again setting Pulse[75] = 123 (costant value) and re-checked. Well this time CRC was txed as 123! This proved that there is no byte corruption in the code, but the problem should be in setting the byte variable Pulse[75].

So I did change the setting of Pulse[75] = 123 to Pulse[75] = W0.lowbyte. Re-checked and it worked! CRC was txed correctly!

Hence I added : Pulse[75] = ~ Pulse[75] (inverting bits) and CRC was still txed as 253!!!!

I have removed Pulse[75] = ~ Pulse[75] and kept the CRC as the low byte of the packet sum that works!

But as I stated in this thread title: "I cannot find the reason for such a strange behavior"

Alberto

[richard]

try as I might I cannot produce any code where
Pulse[75] = ~W0
gives an incorrect result , the problem is elsewhere
I believe you are just masking the real problem/s
my challenge to you is :-
provide some fully compliable code that demonstrates the problem , I would bet you cannot


Pulse[75] = ~W0 converts to a 1 line macro when compiled

NOT?WB  _w0, _Pulse + 00075h

where can that go wrong ?