[time-nuts] FE-5680A OSMT connector / RS232

Hal Murray hmurray at megapathdsl.net
Mon Dec 10 07:25:25 UTC 2012

james at peroulas.com said:
> I'm not able to get it to respond to the 'S' command and when I measure the
> voltage on the RS232 TX pin (#2 from the left) it's always 0v. Shouldn't it
> be -12v when idle?

Newer RS-232 allows 6V rather than 12.

In practice, it's not all that uncommon for designers to save a chip and just 
send 5V CMOS signals.  That works fine for short distances.

If you can get a scope on it, sometimes embedded boxes send out a hello 
message at power up.

I'd also check pin 3 in case you or they got things swapped.

These are my opinions.  I hate spam.

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