SETQ - Quick question for Chip

Comments

• evanh Posts: 8,245

  2019-02-15 - 09:42:50

  I think the first SETQ will never reach the RDLONG. From memory, even a NOP clears it. Same for ALTx instructions.
  

  We have the vastness of the internet and yet billions of people decided to spend most of their time within a horribly designed, fake-news emporium of a website that sucks every possible piece of personal information out of you so it can sell it to others. And they see nothing wrong with that.
• Cluso99 Posts: 15,527

  2019-02-15 - 09:44:36

  May as well also ask, can setq be set more than once and will the new setting overwrite the previous?

  My Prop boards: P8XBlade2 , RamBlade , CpuBlade , TriBlade
  P1 Prop OS (also see Sphinx, PropDos, PropCmd, Spinix)
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• evanh Posts: 8,245

  2019-02-15 - 09:54:39

  Cluso99 wrote: »

  ... will the new setting overwrite the previous?

  More accurately, it will be rearmed because the first SETQ value is already consumed.
  

  We have the vastness of the internet and yet billions of people decided to spend most of their time within a horribly designed, fake-news emporium of a website that sucks every possible piece of personal information out of you so it can sell it to others. And they see nothing wrong with that.
• cgracey Posts: 11,891

  2019-02-15 - 10:03:50

  If the 2nd SETQ gets cancelled, it looks like a NOP, making the RDLONG just read a single long, as if no SETQ was used.
• Cluso99 Posts: 15,527

  2019-02-15 - 10:40:35

  So the SETQ must immediately precede the RD/WR/LONG.
  So no non-executed instructions can intervene.

  My Prop boards: P8XBlade2 , RamBlade , CpuBlade , TriBlade
  P1 Prop OS (also see Sphinx, PropDos, PropCmd, Spinix)
  Website: www.clusos.com
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• ozpropdev Posts: 2,603

  2019-02-15 - 11:07:08

  Instead of

    if_e    setq    #len1-1
    if_ne   setq    #len2-1
            rdlong  cog0,hubptr
  

  you could use

    if_e    altd    zero,#len1-1
            setq    #len2-1
            rdlong  cog0,hubptr
  

  where "zero" is a cog register containg #0

  Melbourne, Australia
• Cluso99 Posts: 15,527

  2019-02-15 - 12:05:25

  I had to settle for

          if_ne   mov     reply,            #cog_len-1    ' set to copy whole cog (496 longs)
          if_e    mov     reply,            #cog_len80-1  ' set to copy 512 bytes (128 longs)       
                  setq    reply                           ' length -1
                  rdlong  cog_start0,       _hubdata      ' copy loaded code into cog
          if_ne   jmp     #$0                             ' NZ: execute loaded cog code
                  jmp     #$020                           ' Z:  execute loaded cog code from $080+
  

  My Prop boards: P8XBlade2 , RamBlade , CpuBlade , TriBlade
  P1 Prop OS (also see Sphinx, PropDos, PropCmd, Spinix)
  Website: www.clusos.com
  P1: Tools (Index) , Emulators (Index) , ZiCog (Z80)
  P2: Tools & Code , Tricks & Traps