In SX Microcontrollers, SX/B Compiler and SX-Key Tool, peterverkaik wrote:

The SX/B command high ra compiles into
  MOV W,#$1F                     ;  high ra
  MOV M,W                       
  MOV !RA,#0                    
  MOV RA,#$FF

If ra was already set to all outputs there is no problem.
If ra however was set to inputs, but the latch holds zeroes,
then changing to outputs makes the pins low
and the mov ra,#$FF makes the pin high.
So there is a (possible) glitch.

I think the order should be
  MOV RA,#$FF
  MOV W,#$1F                     ;  high ra
  MOV M,W                       
  MOV !RA,#0                    
If the pins are already outputs, the pins get the right value.
If the pins were inputs, the pins also get the right value, but without a glitch.

So the order should be: set latch, then set direction.

regards peter

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