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

Thanks for the feedback once again, Jon!  

(Man, I don't see how you get anything done with all the detailed posts you provide!)

I'm still not seeing something, though...

The [b]CLRB MidiOut[/b] only occurs on the start bit.  The other bits 9 bits freely toggle between input and output for on-1/off-0 without performing a CLRB or SETB on the MidiOut port - just with toggling the shadow TRIS registers, as you say.  I could see if it's that way with all bits that are 0, but it only occurs with the start bit.

With a 'scope, I can see the pin's state go to zero on the start bit, as soon as the [b]MOV !RA,IND[/b] is executed, and [i]before[/i] the [b]CLRB MIDIOUT [/b]is executed.  (Experimenters - be forewarned, with OC you need to have the complete circuit to see the port change).

Could it be, it was coded this way in case it was a bidirectional pin to 'initialize' the state, or in case there was more than two 'devices' in the current loop?

Many thanks!

Rodney

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