Depth sounders to show negative numbers

Thanks Doug

See my reply to Glen

Phil


"Doug Dotson" <dougdotson@NOSPAMcablespeedNOSPAMcom> wrote in message
news:PKednQ7nLezufMzfRVn-2A@cablespeedmd.com...
> I've tried the "depth below keel" approach. I found that the depth sounder
> should show the depth of the water itself. Do the various conversions in
> your head. Knowing the true depth helps with setting the anchor, etc.
>
> Doug
>
> "Phil Stanton" <philnoxx RemoveThis @xxstantonfamily.co.uk> wrote in message
> news:4251c4fb$0$94525$ed2619ec@ptn-nntp-reader01.plus.net...
>> Does anyone know if there is a depth sounder which shows a negative
>> depth. OK sounds like a loony question.
>> I have a lift keel boat and want to set the offset when there is no water
>> under the keel with the keel down. Same as all sensible people with fixed
>> keel boats. Easy to do with my Raymarine ST60 Tridata echo sounder. Now
>> if I raise the keel to go into shallower waters, there isn't 7 ft (2.2m)
>> of water in a lot of places on the East Coast of England, I still want to
>> know how much water there is underneath me. Hence I need to find an echo
>> sounder that shows 0.0m with no water under the keel when down, an
>> say -0.7m when the depth is 0.7m less than with the keel fully down.
>> Hence my question. I should have thought with the number of lift keel
>> boats there would be a reasonable demand, and lets face it, it isn't
>> rocket science to make a minus sign show up on a LCD display
>>
>
>
 >> Stay informed about: Depth sounders to show negative numbers 

Phil Stanton wrote:
> Hi Wout
>
> Thanks for the information. I will definitely investigate this further, as
> in addition to the depth problem, I am having problems getting my Laptop to
> talk to the Autopilot. May be a wiring fault, but apparently the ST60 multi
> instrument has NMEA In and Out.

A good way to trouble shoot NMEA data problems is to use the
Hyperterminal communications utility included with Windows. That will
show you the NMEA data flow as scrolling ascii text strings. And the
strings can even be saved to a text file for later study.

To use it, select the COM port your NMEA data is on in the "Connect
using:" box. Then change the settings to 4800 baud, 8 data bits, parity
to none, and stop bits to 1. If your NMEA data is at a different baud
rate you may have to change that, the display will be repeated garbles
when that happens. Sometimes you can check the setup on your NMEA
talkers to see what baud rate is being used, they all need to be the same.

Seeing the NMEA data strings tells you your laptop setup is working and
can help you isolate the problem.

There is a known problem with Windows misidentifying a GPS or NMEA input
as a serial mouse. If you go to the device manager find a serial mouse
there, disable it and leave it disabled and that will not happen again.

Jack

--
Jack Erbes in Ellsworth, Maine, USA - jackerbes at adelphia dot net
(also receiving email at jacker at midmaine.com)
 >> Stay informed about: Depth sounders to show negative numbers 

Sorry for delay in replying. Couldn't check it out till the weekend. Bags of
input from a GPS to the HyperTerminal, but nothing from the ST60 Multi. I
think it could be faulty

Thanks for steering me towards the HyperTerminal. I had never heard of it.

Phil


"Jack Erbes" <jackerbes.TakeThisOut@adelphia.net> wrote in message
news:KLKdnZcP25CCRc7fRVn-2w@adelphia.com...
> Phil Stanton wrote:
>> Hi Wout
>>
>> Thanks for the information. I will definitely investigate this further,
>> as in addition to the depth problem, I am having problems getting my
>> Laptop to talk to the Autopilot. May be a wiring fault, but apparently
>> the ST60 multi instrument has NMEA In and Out.
>
> A good way to trouble shoot NMEA data problems is to use the Hyperterminal
> communications utility included with Windows. That will show you the NMEA
> data flow as scrolling ascii text strings. And the strings can even be
> saved to a text file for later study.
>
> To use it, select the COM port your NMEA data is on in the "Connect
> using:" box. Then change the settings to 4800 baud, 8 data bits, parity
> to none, and stop bits to 1. If your NMEA data is at a different baud
> rate you may have to change that, the display will be repeated garbles
> when that happens. Sometimes you can check the setup on your NMEA talkers
> to see what baud rate is being used, they all need to be the same.
>
> Seeing the NMEA data strings tells you your laptop setup is working and
> can help you isolate the problem.
>
> There is a known problem with Windows misidentifying a GPS or NMEA input
> as a serial mouse. If you go to the device manager find a serial mouse
> there, disable it and leave it disabled and that will not happen again.
>
> Jack
>
> --
> Jack Erbes in Ellsworth, Maine, USA - jackerbes at adelphia dot net
> (also receiving email at jacker at midmaine.com)
 >> Stay informed about: Depth sounders to show negative numbers 

Phil Stanton wrote:
> Sorry for delay in replying. Couldn't check it out till the weekend. Bags of
> input from a GPS to the HyperTerminal, but nothing from the ST60 Multi. I
> think it could be faulty
>
> Thanks for steering me towards the HyperTerminal. I had never heard of it.
>

You're welcome. Its been a freebie with Windows as long as I can
remember, great to use as a console for talking to various devices like
switches and routers, good for testing modems, and trouble shooting some
other devices.

As an added note, someone on another group pointed out to me that
Hyperterminal will not always work as I described it. It will work for
receive only connections but if the sending device expects that there
will two way communications it will not or may not work. I'm not that
smart about RS-232 communications and can't further explain that but it
sounds reasonable to me. Nothing else in Windows is guaranteed to
always work, why should that? :>)

But it has been a good trouble shooting tool for me in checking out GPS
to PC connections.

Do you know that your ST-60 is communicating in a RS-232 serial mode?
If that is a SeaTalk instrument or in that mode, it won't work because
that is Raymarine's proprietary flavor of RS-232 or something like that.

Jack

--
Jack Erbes in Ellsworth, Maine, USA - jackerbes at adelphia dot net
(also receiving email at jacker at midmaine.com)
 >> Stay informed about: Depth sounders to show negative numbers 

Hi Jack

There doesn't seem to be a way of specifically setting the ST60 to output in
RS-232 serial mode. In addition to the SeaTalk connections on the back of
the instrument there are 2 pairs of connections marked NMEA Out and NMEA In.
In addition there is a setting on the instrument for "NMEA Output ON". It
all sounds terribly logical..
Have contacted RayMarine and wait their opinion.

Thanks

Phil

"Jack Erbes" <jackerbes RemoveThis @adelphia.net> wrote in message
news:mPidnfR-_vQresTfRVn-pA@adelphia.com...
> Phil Stanton wrote:
>> Sorry for delay in replying. Couldn't check it out till the weekend. Bags
>> of input from a GPS to the HyperTerminal, but nothing from the ST60
>> Multi. I think it could be faulty
>>
>> Thanks for steering me towards the HyperTerminal. I had never heard of
>> it.
>>
>
> You're welcome. Its been a freebie with Windows as long as I can
> remember, great to use as a console for talking to various devices like
> switches and routers, good for testing modems, and trouble shooting some
> other devices.
>
> As an added note, someone on another group pointed out to me that
> Hyperterminal will not always work as I described it. It will work for
> receive only connections but if the sending device expects that there will
> two way communications it will not or may not work. I'm not that smart
> about RS-232 communications and can't further explain that but it sounds
> reasonable to me. Nothing else in Windows is guaranteed to always work,
> why should that? :>)
>
> But it has been a good trouble shooting tool for me in checking out GPS to
> PC connections.
>
> Do you know that your ST-60 is communicating in a RS-232 serial mode? If
> that is a SeaTalk instrument or in that mode, it won't work because that
> is Raymarine's proprietary flavor of RS-232 or something like that.
>
> Jack
>
> --
> Jack Erbes in Ellsworth, Maine, USA - jackerbes at adelphia dot net
> (also receiving email at jacker at midmaine.com)
 >> Stay informed about: Depth sounders to show negative numbers 

Phil Stanton wrote:

> Hi Jack
>
> There doesn't seem to be a way of specifically setting the ST60 to output in
> RS-232 serial mode. In addition to the SeaTalk connections on the back of
> the instrument there are 2 pairs of connections marked NMEA Out and NMEA In.
> In addition there is a setting on the instrument for "NMEA Output ON". It
> all sounds terribly logical..
> Have contacted RayMarine and wait their opinion.
>

Sounds like you're using the right connections then. NMEA is RS-232 by
definition. The ST-60 NMEA Out and NMEA In would normally be connected
to the RS-232 RXD and TXD. If you have not tried it, reversing the
connections is worth a try. The connections are made so that the NMEA
output goes to a RS-232 input and the NMEA input comes from an RS-232
output giving you the following:

NMEA Out --- RS-232 RXD
NMEA In --- RS-232 OUT

Various terms are used for the connections, the semantics can be
confusing, and human error can rear its head. So swapping the two leads
has become a routine step in trouble shooting for me.

A final thing. If one of the devices has connections for both a
"Ground" and for "Power (-)", sometimes connecting those two together
will make it work. You can test that with a temporary jumper.

An example of that was the wiring for a cable I made for NMEA serial
connection between my iPAQ 3675 and Magellan 330M. It simply would not
work until the shield on the 330M cable and lead called "Ground" on the
3675 were connected to the negative power lead.

Jack

--
Jack Erbes in Ellsworth, Maine, USA - jackerbes at adelphia dot net
(also receiving email at jacker at midmaine.com)
 >> Stay informed about: Depth sounders to show negative numbers 

"Jack Erbes" <jackerbes.DeleteThis@adelphia.net> wrote in message
news:VvCdnYCqX_-o58ffRVn-gg@adelphia.com...
> Sounds like you're using the right connections then. NMEA is RS-232 by
> definition.

Wrong. NMEA is RS-422 by definition. And if everyone would have adhered to
that standard, we wouldn't have so many problems with intermixing RS-422 and
RS-232 devices. Every NMEA device should have an output labeled Out A and
Out B and an input named In A and In B. NMEA standard, chapter 3. But it was
the manufacturers who made a mess of it.
Take a look at www.shipmodul.com/en/connections.html for primer on NMEA
connections.

Meindert
 >> Stay informed about: Depth sounders to show negative numbers 

Meindert Sprang wrote:
> "Jack Erbes" <jackerbes DeleteThis @adelphia.net> wrote in message
> news:VvCdnYCqX_-o58ffRVn-gg@adelphia.com...
>
>>Sounds like you're using the right connections then. NMEA is RS-232 by
>>definition.
>
>
> Wrong. NMEA is RS-422 by definition. <snip>

Oops. I think I meant to say it was serial by definition. Thanks for
clarifying that.

Jack

--
Jack Erbes in Ellsworth, Maine, USA - jackerbes at adelphia dot net
(also receiving email at jacker at midmaine.com)
 >> Stay informed about: Depth sounders to show negative numbers 

"Meindert Sprang" <mhsprang DeleteThis @NOcustomSPAMware.nl> wrote in
news:115l8ai8he82n6d@corp.supernews.com:

> we wouldn't have so many problems

Actually, too bad NMEA didn't look ahead and use RS-485 as the standard. I
supports 32 talkers and 32 listeners on a single line.....

Er, ah, of course we wouldn't need to buy Meindert's MULTIPLEXERs under RS-
485. 32 talkers is plenty for most boats.....(c;
 >> Stay informed about: Depth sounders to show negative numbers 

"Jack Erbes" <jackerbes.RemoveThis@adelphia.net> wrote in message
news:nvOdnbr-wrM9e8ffRVn-iA@adelphia.com...
> Meindert Sprang wrote:
> > Wrong. NMEA is RS-422 by definition. <snip>
>
> Oops. I think I meant to say it was serial by definition. Thanks for
> clarifying that.

Ah, easy slip of the mind, serial, RS-232, all sounds the same

Meindert
 >> Stay informed about: Depth sounders to show negative numbers 

"Larry W4CSC" <noone RemoveThis @home.com> wrote in message
news:Xns9635AF4AB39Cw4csc@63.223.7.253...
> Those problems are usually because of the hardware connections associated
> with CTS (clear to send) and RTS (request to send) lines not being held
> high. RS-232 is made for hardware handshaking between devices so the
> listening device can stop the transmission when its buffer (bit bucket?)
is
> full. It goes way back to really dumb terminals that have no storage in
> them for data. Jumpers added to the DB9 or DB25 connectors can make it
run
> wide open to hyperterm on dumb data....er, ah, like NMEA..(c;

In Hyperterminal, you can goto File->Properties, click the button Configure,
goto Flow Control and select None.

And at the Properties page, tab Settings, goto ASCII setup and select "Send
line ends with line feeds" in order to send a line feed when you type an
NMEA sentence manually.

But a much better substute for HyperTerminal is TeraTerm.

Meindert
 >> Stay informed about: Depth sounders to show negative numbers 

"Larry W4CSC" <noone DeleteThis @home.com> wrote in message
news:Xns9635B02BAA3C6w4csc@63.223.7.253...
> "Meindert Sprang" <mhsprang DeleteThis @NOcustomSPAMware.nl> wrote in
> news:115l8ai8he82n6d@corp.supernews.com:
>
> > we wouldn't have so many problems
>
> Actually, too bad NMEA didn't look ahead and use RS-485 as the standard.
I
> supports 32 talkers and 32 listeners on a single line.....
>
> Er, ah, of course we wouldn't need to buy Meindert's MULTIPLEXERs under
RS-
> 485. 32 talkers is plenty for most boats.....(c;



Meindert
 >> Stay informed about: Depth sounders to show negative numbers 

"Phil Stanton" <philnoxx RemoveThis @xxstantonfamily.co.uk> wrote in message
news:425a30f3$0$27833$ed2619ec@ptn-nntp-reader03.plus.net...
> Hi Jack
>
> There doesn't seem to be a way of specifically setting the ST60 to output
in
> RS-232 serial mode. In addition to the SeaTalk connections on the back of
> the instrument there are 2 pairs of connections marked NMEA Out and NMEA
In.
> In addition there is a setting on the instrument for "NMEA Output ON". It
> all sounds terribly logical..
> Have contacted RayMarine and wait their opinion.
>
> Thanks
>
> Phil
>
> "Jack Erbes" <jackerbes RemoveThis @adelphia.net> wrote in message
> news:mPidnfR-_vQresTfRVn-pA@adelphia.com...
> > Phil Stanton wrote:
> >> Sorry for delay in replying. Couldn't check it out till the weekend.
Bags
> >> of input from a GPS to the HyperTerminal, but nothing from the ST60
> >> Multi. I think it could be faulty
> >>
> >> Thanks for steering me towards the HyperTerminal. I had never heard of
> >> it.
> >>
> >
> > You're welcome. Its been a freebie with Windows as long as I can
> > remember, great to use as a console for talking to various devices like
> > switches and routers, good for testing modems, and trouble shooting some
> > other devices.
> >
> > As an added note, someone on another group pointed out to me that
> > Hyperterminal will not always work as I described it. It will work for
> > receive only connections but if the sending device expects that there
will
> > two way communications it will not or may not work. I'm not that smart
> > about RS-232 communications and can't further explain that but it sounds
> > reasonable to me. Nothing else in Windows is guaranteed to always work,
> > why should that? :>)
> >
> > But it has been a good trouble shooting tool for me in checking out GPS
to
> > PC connections.
> >
> > Do you know that your ST-60 is communicating in a RS-232 serial mode? If
> > that is a SeaTalk instrument or in that mode, it won't work because that
> > is Raymarine's proprietary flavor of RS-232 or something like that.
> >
> > Jack
> >
> > --
> > Jack Erbes in Ellsworth, Maine, USA - jackerbes at adelphia dot net
> > (also receiving email at jacker at midmaine.com)
>
>
Hi,
I was under the impression that the whole exercise was to determine if the
ST60 Multi instrument would display a negative depth if received in a NMEA
depth sentence.
For this test, you want to connect the Transmit line of the PC Com port to
NMEA IN. Connect your PC Com port pins 3 and 5 to NMEA IN + and NMEA IN -
and transmit a $SDDBT sentence from Hyperterminal to the ST60 Multi
instrument.
Start Windows program Notebook and type the following NMEA sentence:
$SDDBT,-2.0,f,,,,*22 Press Enter and save this text in a file. The
value -2.0 represents a "negative" depth of 2.0 feet.
Start Hyperterminal with the PC connected to the ST60 instrument as
described above. Click on Transfer at the top of the Hyperterminal screen
and select "Send Text File". Find the .txt file you saved with Notebook and
transmit. Repeat this a few times and it will become clear if the ST60 Multi
is willing to display a negative value. Try a positive depth first to check
if you've got the connections right, e.g. $SDDBT,3.0,f,0.9,M,0.5,F*09

Wout
 >> Stay informed about: Depth sounders to show negative numbers