[time-nuts] Thunderbolt and USB to RS232 converters

[Arnold Tibus]

Hello all Thunderbolt enthusiasts, 

I follow with great interest all the comments and remarks. 
I have as well a Thunderbolt and I am running it successfully since 
a few days under WinXP SP2 directly on Com1 and with several 
USB/RS232 converter I/Fs. Of course all the necessary drivers for my 
USB/Ser adapters (Prolific v. 2.0.0.18 and CH341PT.DLL 
& CH341SER.SYS from winchiphead.com/cn) are installed.
Most of the day it runs with 6 to 8 satellites, the antenna not yet on the roof.

Fortunately Trimble designed the I/F protocols quite straight in line and 
one can use some features of programs for other models which are not 
in Tboltmon.. I tried severals and found, beside - Tboltmon.exe 
(v2.60, Thunderboltmonitor program) as well very interesting and helpful :

- DSPMon.exe (v1-53) DSP GPS Timing Monitor

- TR_MON.exe  Timing Receiver Monitor 
(the only one with instructiv help file)

- trimblemon.exe (v1-06-0) Trimble GPS Monitor 
with instruction file as pdf explaining
"Installing the FTDI USB/Serial Driver Software."
"The new Trimble GPS Monitor (TGM) application is a tool 
that can replace many of the previous 
monitor
 and 
chat
 
programs used for Trimble Embedded and Resolution T products."
A nice gimmick is eg. the real time Google on line Sat map etc. 

Attention: I don't know if it is possible to upset the Thunderbolt 
with incorrect instructions uploaded, but I do not think so, 
pse do not make me responsible!

Digging around I found a good helper for the ser. interface connection 
and setting problems:

You do not know how to find the right com port setting? 
There is a way with 'Trimble GPS Monitor' v. 1.06.0 :
it does run a test with all possible parameters on the selected port 
of the list.

Connect the GPS RX to the desired Com Port eg. via an USB/RS232 
converter,
Start 'Trimble GPS Monitor 1.06.0 _07/2008 .exe' (no installation necessary),
'Initialize',: 'Detect Receiver', 
Select a COM Port out of the list, tick 'Protocols': 
'TSIP' & 'Check even parities', follow instruction at 'Status' to start,
start 1st com port and repeat it with next port no.until the program does 
report the successful detection of the GPS-Receiver showing port 
parameters of receiver.
Accept to connect to it and start monitoring. 
In fact,
the default parameters for Thunderbolt seem to be 9600-8-Odd-1. 

These parameters may then be modified under 'Configure', 
'Receiver Configuration', 'Port Configuration' to eg. Parity 'None' (usual) 
and saved with 'Set and Save Configuration' into non volatile memory.

Now you can exit this program and start 'Thunderbolt Monitor' 
(v. 2.60/1999), you are then asked to set the the now known port no 
(eg. 13), the program communication should start nominal.

As I understand, once properly configured the Thunderbolt does run 
without the need of the PC, if the position is not changed. 
The Oscillator continue to run with the (last?) afc value stored in 
memory.

The details for best configuration I don't know yet, I hope there 
will be more hints given by the experts here in the group. 
I keep watching !

I am running the TB with a prolific USB to Serial adapter (result: com9) 
and a cheap ftdi based USB2 adapter (com13) very smooth. Naturally 
it does work as well directly connected to the db9pin port com1 on the PC, 
always using a direct 1:1 wired 9p-9s connection and not a wire crossing 
(null modem) cable! 

I connected both USB/RS232 adapters simultaneously to my Laptop 
getting 3 free serial ports available for the GPS Receivers, com1, com9 
and com14 (attention, the port numbers may change when plugging in 
and out, sometimes you may have to search for new devices). 
Thunderbolt Monitor does show all the assigned ports at the right side 
column for com ports 1 to 16. 
Clicking in the empty fields the assigned ports turn yellow (and remain on, 
the designated and selected GPS-port turns green.
That way it is possible to run several GPS devices with different control 
software.

I hope that  I could help somebody with these small hints for the first steps.

I find it a good idea to design some (small?) h/w to command the 
Thunderbolt without the need of a PC.

good luck and fun experimenting,
Thank you Tom and all the others involved here in the group buy of 
Thunderbolt together with the adequate power supply!

regards,
Arnold T.


On Tue, 24 Jun 2008 16:56:45 +0200, Jeroen Bastemeijer wrote:

>Dear All,

>More and more people are starting to play with the Thunderbolts. I
>already received mine :-)  Now playing around with them.

>First I powered it up and connected it to the normal serial port of the
>PC. The Thunderbolt behaved fine, self survey took some time, because
>the antenna is inside a concrete building with very limited view to the sky.

>However, next I did a test with the same Thunderbolt but now it was
>connected to a USB to Serial converter (brand is Sweex). After
>switchinhg it off and on, I expected the same behaviour as when it was
>connected to the "real" serial port. But... it started to behave very
>strange... instead of starting a normal survey, it started disciplining
>after a couple of minutes (almanac was not even valid). The DAC-voltage
>clipped to the power rail, and the SV and AMU-fields remained "?". 
>Resetting (hot, cold, factory default) didn't make any difference.
>When power cycling the unit and connecting it back to the normal serial 
>port the normal behaviour returned. I assume it has something to do with 
>the USB to serial converter. Is there anyone else with similar 
>experience? Or who has used a USB to serial converter with succes?

>Thank you, best regards,

>Jeroen

>-- 
>Ing. Jeroen Bastemeijer

>Delft University of Technology
>Department of Electrical Engineering
>Electronic Instrumentation Laboratory
>Mekelweg 4, Room 13.090
>2628 CD Delft
>The Netherlands

>Phone: +31.15.27.86542
>Fax: +31.15.27.85755
>E-mail: J.Bastemeijer at TUDelft.nl
>GPS: Lat N52.00002 Lon E4.37157 Alt 46.2m