I used a hand-compiled statement in assembly for a large switch statement in
the CCS compiler.
This is a routine to send one bit of an IrDA compatible infrared signal.
It's called 19200 times per second; other code turns off the bit after a
short (1 or 2 microsecond) delay, and refills the "char_to_send".  If your
code has varying lengths, a jump table might be a better alternative.

#inline
void send_ir() {
  //if (bit_to_send > 27) bit_to_send = 0;

  pclath = 0; //because this code is within the global interrupt routine
  #asm
  movf bit_to_send,w
  addwf pcl,f

  nop
  bsf portc.tx
  goto end

  btfss char_to_send,0
  bsf portc.tx
  goto end

  btfss char_to_send,1
  bsf portc.tx
  goto end

  btfss char_to_send,2
  bsf portc.tx
  goto end

  btfss char_to_send,3
  bsf portc.tx
  goto end

  btfss char_to_send,4
  bsf portc.tx
  goto end

  btfss char_to_send,5
  bsf portc.tx
  goto end

  btfss char_to_send,6
  bsf portc.tx
  goto end

  btfss char_to_send,7
  bsf portc.tx
  goto end

  clrf bit_to_send
  clrf char_to_send
  goto exit

  #endasm
  end:
  bit_to_send+=3;
  exit:
  return;
}

----- Original Message -----
From: "Thys" <thys@DEMAN.CO.ZA>
To: <PICLIST@MITVMA.MIT.EDU>
Sent: Wednesday, January 22, 2003 10:40 AM
Subject: [PIC] HT-PIC and large switch statements?


> Hi,
> I want to re-use old code that contains large switch-statement with about
> 30 cases consecutively numbered 0,1,2...
>
> HT-PIc ver 7.8 compiler implemented this as a jump table.
> With v 8.01 it is done as a sequence of tests. Net result is that time
> taken to execute cases at the end is far to long now, and code does not
> work any more.
> Is there a way to force creation of a jump table , or other coding methode
> ( inline assembler ??)
>
>
>
> Any ideas ?
>
> Thys
>
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