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

Since those having trouble seem to be applying more guesswork than science I'm going to guess that the ghost of Mickey Mouse (I live near the Disney studio) is watching over my desk, making this work for me but not for you!   :tongue:   (Relax, I'm poking a bit of fun to lighten up this thread)

On the odd event that I just got lucky after four hours of [u]work[/u] last Saturday I removed a project from my PDB, reconnected the SX to the BS2, and then re-ran the programs.  Thank you, Mickey! -- [u]they work[/u] yet again.  I've even taken a picture of my setup and used different colored wires so that you can see exactly how I did it.  For those that want to pay travel and per diem, I'm happy to bring my setup to your home to prove it to you!   :smilewinkgrin: 

For review (warning: science stuff):

* True mode means the line idle state is high.  A start bit will go low and the data bits, which arrive LSB first, will have their normal polarity (i.e., a "1" is high, a "0" is low); the stop bit is at the line idle state (high for True mode).  See attached image.

* True mode communications drives the TX and CTS outputs all the time -- this means that no pull-ups are required for this program to work properly.  It also means that we need to initialize these pins as outputs and high (both sides do this).

* True mode is not a "cheat" -- it's used when the TX line of one device connects to the RX of another and comms flows in one direction only (on that connection).  Why use Open True mode, then?  We only need this mode when using half-duplex communications on the same wire, that is, the TX line can become an RX line and vice-versa (like with the PSC); by using Open baud modes we can prevent an electrical conflict if both sides try to transmit at the same time.


As a reminder... frustration rarely brings solutions.  I walked away from my desk more than once on Saturday to clear my head when I got frustrated.  After the first program worked, everything after flowed very easily.  It will for you, too -- if you just hang in and not give up.

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