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