[time-nuts] how to open a Trimble mushroom ?

[Hal Murray]

> Seem to recall they may be rs422.

Trimble has/had at least 2 units like that: Palisade and Acutime.  There have 
been several variations of the Acutime.

Trimble had a development kit for the Palisade.  It was a little box with 
RS-422 to RS-232 converters, a DB-25 on the back, 2 DE-9s and a BNC on the 
front.  (and cables and such)
  ftp://ftp.trimble.com/pub/sct/embedded/bin/Manuals/Old%20Manuals/PALISADE.PD
F

There are 5 signals:
  PPS
  Tx-A, Rx-A
  Tx-B, Rx-B

The B channel is reasonably normal.  You can send and receive messages.

The A channel is different.  The Tx (to Palisade) signal is for timing, not 
data.  The development kit wires it up to one of the modem control signals.  
When you flap that signal, it sends you back a message with the time that the 
signal flapped.  If your RS-422/232 converter wired Tx-Tx, you can send a 
null byte.

  

-- 
These are my opinions, not necessarily my employer's.  I hate spam.