Another way to left shift a 32 bit data?

[Ioannis]

Since using LONGs in the program will slow down the execution of the program, I am reluctant to use longs. Also the PIC that curretly is used is 16F series.

So, seems better to spend some bytes in RAM or FLASH and have immediate response.

Ioannis

[Art]

That’s what I mean. Still a more difficult problem than appears, or more than it intuitively feels like it should be, if speed is the goal.
The extra 6 bits returned by a single 14 bit READCODE are useless to you because of the time taken to extract them.
The word variable you get to use to address program memory is also useless to you because you only needed a 32 bit index (or 32x4).
I’d be interested to hear how you end up tackling it.

[Ioannis]

It is indeed a complex problem. In any option chosen, there would be some overhead lower or higher I guess.

I think I will end up in the asm code to rotate the variables.

Ioannis

[richard]

you can set or clr any bit in an array
dis var byte [4]

dis.0[x] = 1 ; will set bit x in array dis where x=0 to 31

or make a user command something like this (untested)
USERCOMMAND "SETBIT" ; BIT,VALUE

SETBIT?CC macro Bitin,Val
if Bitin <32
  if Bitin > 23
k=3
  elseif  Bitin > 15
k=2
  elseif  Bitin > 7
k=1
  elseif  Bitin <8
k=0
  endif
b=Bitin-k*8


  if Val >0
  bsf _dis+k,b
  else
  bcf  _dis+k,b
  endif
endif
endm

not sure if user cmd is really useful here

[Ioannis]

Thanks Richard.

Interesting approach!

Ioannis

[Art]

I don’t yet know if I’ve wrecked it in basic.

shifter byte
offset byte
array byte[7]


shifter = 11
offset = shifter >> 3            // byte in array to pass to whatever needs the 4 byte result, in this case 2
array[3] = 1<<(shifter & 7)      // Set it to 00000000 (00000000 00000000 00001000 00000000) 00000000 00000000
‘dostuff with array[offset]

[Ioannis]

I could not follow that...

Ioannis