"Thomas, without connecting RXA to the
TX of SoftwareSerial port used for sonar
it is not working properly. In this moment
I have the following:
SoftwareSerial sonar(6, 5, true) and TXA is
connected to pin 6 (RX on serial) and RXA is
connected to pin…"

"Yes, at the end of the cable on red wire I have a
black label sticked on it and there it is written
the explanation of each color wire. And there is
an RXA and an RXB. In the manual these 2 wires
appear to be spare. RXA is white and RXB is…"

"I didn't found in the manual minimum depth, in any case
it is showing me the real depth of the barrel, 0,4 meters.
On the Arduino Mega you are using a software serial or a
hardware serial? Did you used RX wire from Intelliducer?
In my case I used…"

"In the manual of Intelliducer RX wires are not stated,
the 2 wires that are RX apear to be, in the manual,
spare wires. But is normal to use TX and RX, after all
is a serial connection.
Did you use also RX wire?

In any case I managed it after all,…"

"Ok, I managed to solve it. The cable from Intelliducer is
having another 2 wires, RXA and RXB. I connect TXA and RXA to
the softwareserial pins and is working. When I am not connecting
RXA wire is not working.

Regards,
Dragos"

"Thanks anyway Thomas...
I've checked topic of Burkhard, it was one of the first
topics I read when I joined the forum, I didn't found there
any .ino file, the only one I have is yours. I've tried it
but without succes. I can output the NMEA data…"

"I am using a NMEA 0183 Thruhull Intelliducer. If I am connecting TXB
wire from the Intelliducer I get no data. I get data only with TXA
and SoftwareSerial set for inverted signal. But the data is not
intelligibile, I can see from time to time SDDBT…"

"As I said I tried to test in a barrel, I can see sometimes
the depth of the barrel (0,4 metres) in the output of sonar,
but the big problem is that softwareserial is giving me a lot
of strange characters. I cannot see a valid NMEA0183 output…"

"In my case the softwareserial defined for sonar is outputting something
only if I am using inverted parameter, SoftwareSerial sonar(6, 5, true).
But I have a lot of strange characters, among them I can see some times
SDDBT and SDDPT, without $…"

"Hello Thomas,

Do you know what is the minimum depth that Intelliducer can read?
I was trying your program using an Arduino Uno and Adafruit GPS data logger
and is not working, I have tried it in a small barrel of around 40 cm depth.
Also do you…"

"Hello Thomas,

Nice work, thanks for sharing :)

I have a similar project for a bait boat and I will use Garmin Intelliducer and
Adafruit GPS/Data Logger, I checked the code that you posted and I have a question:
- how did you connect the interface…"