converting coginit code to a call

Comments

• JonnyMac Posts: 8,918

  2022-01-25 16:51 edited 2022-01-25 16:52

  The call() instruction only supports an address parameter so that's probably not going to work for you. Will an inline method work? You could do something like this:

  pub pasm_main(p_par) : result
  
    org
                  mov       ptra, p_par
                  {
                    rest of your pasm code here
                  }
    end
  
• JonnyMac Posts: 8,918

  2022-01-25 17:06

  After reading the docs a bit more, it seems like you just have to add a second line: pass your address for ptra in an available register. I did this simple test:

  pub call_test() | ticks
  
    ticks := MS_001 * 100
  
    pinhigh(56)                                                   ' Eval LEDs off
    pinhigh(57)
    repeat
      call(@blip56)
      waitms(400)
  
      pr0 := @ticks                                               ' pass address via pr0
      call(@blip57)
      waitms(400)
  
  
  dat
                  orgh
  
  blip56          drvnot    #56
                  waitx     ##(MS_001 * 100)
    _ret_         drvnot    #56
  
  
  dat
                  orgh
  
  blip57          rdlong    pr0, pr0
                  drvnot    #57
                  waitx     pr0
    _ret_         drvnot    #57
  

  In your case, the first line of your pasm code would be:

          mov     ptra, pr0
  
• DarkInsanePyro Posts: 31

  2022-01-25 17:15 edited 2022-01-25 17:17

  One of my libraries uses pre-loaded (via regload) PASM extensively and uses calls to execute assembly routines. There are 8 registers allocated that have symbols defined in both Spin2 and PASM so they can be shared. I use these registers to pass parameters.

  Example snippet from my library:

  PUB Read(ptr, size, timeout) : actsize | tocnt
  
  '' Reads data from the receive buffer, returning early if the timeout condition is met.
  ''
  '' Arguments
  ''   ptr      pointer to memory
  ''   size     amount of data to be read
  ''   timeout  time, in milliseconds, allowed to block for until returning
  ''            also accepts piCommon.TIME_IMMEDIATE and piCommon.TIME_INFINITE
  ''
  '' Returns:
  ''   number of bytes actually read
  
    PR0 := ptr
    PR1 := size
    PR2 := piCommon.TimeoutToCT(timeout)
    call(#read_asm)
    actsize := size - PR1
  

  Then in the PASM you can access the registers symbolically using PRx (PR0, PR1, etc.).

  Per the Spin2 documentation:

  $1D8..$1DF, which are general-purpose registers, named PR0..PR7, available to both PASM and Spin2 code.

  Pre-edit, looks like I was beat to the punch but figure I'd still submit it to say I vote in favor of what JonnyMac stated. It has been working out for me.
• kwagner Posts: 48

  2022-01-25 17:17

  Either of those should work. I'll give them a try, thanks!

  Edit: Replied same time as DarkInsanePyro. That's great info as well.