Clearing my code: Accessing variables between cogs

jmspaggi

Hi all,

In my main program, I have some variables declaration:

VAR
  long lfNumber ' How many files do we have in the current directory
  long lfBuffer [c#bufferedFilesName * c#maxLenghtFileName / 4] ' Buffer for file names to display
  long lfCurrent ' Which file, in the buffer, we are pointing at.
  long lfFirst   ' Which file is the first in the buffer. IE, if lfFirst = 10, then buffer contain files from 12 to 12+bufferedFilesName
  long lfChangeDirectory ' $FFFF= Do nothing. $FFFE= One directory up. everything else: Move to the x directory in the current folder.
  long lfPlayFile ' $FFFF= Do nothing. else: Play the file x.

I have a cog which have to handle the SD card and will update/read those variables, so I call it that way:

  sd.start (@lfNumber)

On the cog side, here is the way I'm ready/updating those variables:

      if LONG[lf_number_addr+constant(4+c#bufferedFilesName*c#maxLenghtFileName)] < c#bufferedFilesName
        LONG[lf_number_addr+constant(4+c#bufferedFilesName*c#maxLenghtFileName)]++ '' lfCurrent++
      else
        LONG[lf_number_addr+constant(4+c#bufferedFilesName*c#maxLenghtFileName)+4]++
      LONG[lf_number_addr+constant(4+c#bufferedFilesName*c#maxLenghtFileName+4+4+4)] := LONG[lf_number_addr+constant(4+c#bufferedFilesName*c#maxLenghtFileName+4)] + LONG[lf_number_addr+constant(4+c#bufferedFilesName*c#maxLenghtFileName)] - 1 ''lfPlayFile := lfFirst + lfCurrent - 1

... No comments! I'm sure there is an easier and cleaner way to do that.. Because each time I have to update one of those variables, I have to copy this LONG statement

Is there another way to do what I'm doing here?

Thanks,

JM

mpark

You could call sd.start with more pointers:

sd.start( @lfNumber, @lfBuffer, @lfCurrent, @lfFirst, @lfChangeDirectory, @lfPlayFile )

In sd.start you'd have, in addition to lf_number_addr, lf_buffer_addr, lf_current_addr, etc.

Alternatively, you could just pass @lfNumber and then compute the other addresses at the beginning of sd.start:

lf_buffer_addr := lf_number_addr + 4
lf_current_addr := lf_buffer_addr + constant(c#bufferedFilesName*c#maxLenghtFileName)
lf_first_addr := lfCurrent + 4
etc.

Then you could write something like this:

if LONG[lf_current_addr] < c#bufferedFilesName
        LONG[lf_current_addr]++

Btw, there's a typo in c#maxLenghtFileName.

Mike Green

You could also define some local constants like

CON
bFN = c#bufferedFilesName
mLFN = c#maxLengthFileName
plus = bFN + mLFN

jmspaggi

Thanks for your replies.

I understand for the CON section. I can also rename maxLengthFileName mLFN directly in c. But I like verbose things

Regarding adding the variables lf_buffer_addr, lf_current_addr and lf_first_addr to the VAR section, that will add 4 bytes per variables And I would like to avoid that. Is there a way to reference it directly?

Since I have only one instance of this object, is there something like the "#" but for the variables and not only the constrantes?

Thanks,

JM