Picaxe Kayak Control Project


Senior Member
hi folks,
This project describes a kayak control system my buddy & I built last winter. We have enjoyed using it all summer & thought it might be interesting for folks to see just how much functionality could be squeezed out of a Picaxe processor.

I attempted to fully document the project, but the document quickly became book size, so I am posting a rather terse description of the project in the attached pdfs.

Sometimes one idea seems to just spawn another (& another), so by the time we were done, we had developed a plug & play control bus (KYK I2C) that works across Picaxe variants as well as a nice Picaxe project development system.

Since posting the entire project is impossible given the severe pdf attachment size restrictions, I am posting a (more or less) synopsis.

If anyone is interested in any of the boards illustrated in the project, let me know & I can do a per-device posting. All the boards shown are single-sided (albeit with some topside jumpers) & can be made fairly easy at home. Most PCB layouts were done with DipTrace & some were done with the rather ancient (but still by far the best) Tango. However, all can be uploaded as .pdf files.

Sorry I could only upload a glimpse of the project, but it only allowed 2 attachments per post.



Senior Member
Very nice project. Exceptionally well organized program for a picaxe.

Can you provide some pics of the kayak, trolling motor, and steering controls? I ask as someone who has kayaked for 47 years, but whose shoulders are now too wrecked to do much paddling.


Senior Member
Very nice project. Exceptionally well organized program for a picaxe.

Can you provide some pics of the kayak, trolling motor, and steering controls? I ask as someone who has kayaked for 47 years, but whose shoulders are now too wrecked to do much paddling.
hi Ibenson,
I attached a small .pdf showing how trolling motor is mounted.
I thought I could post the whole project but the file size restriction won’t allow it. Guess it will be one piece at a time as needed. The construction files have a lot of pics, so not sure I want to break them into little pieces. May have to have a plan B if anyone gets interested (post to Native site?).

“Picaxe Kayak Control System part 1.pdf” contains info on how to operate the controller.
By the way, I’ve been using the Picaxe controller since early spring & I’ll never go back to paddling/pedaling. You just drop a line each side of yak, then sit back, smoke a cigar, listen to music, enjoy the quiet ride.



Senior Member
Certainly a nice project.

I don't quite understand taking a normally 3-wire bus and making it an 8(or more)-wire bus.
hi Tex,
See “Picaxe Kayak Control System part 2.pdf” for explanation of KYK bus.

The 3-wire I2C bus is not fault-tolerant. This means if the I2C bus locks up, the Picaxe loses control of other devices on the bus (bad news if you’re controlling motors or actuators).

The KYK I2C adds control signal AOE that can be used to shut off power to motors, valves, whatever, in case of an I2C bus fault etc. SRST (system reset) can also hard-reset many devices. It’s a safety thang’.
A cable comes unplugged or Picaxe goes belly-up, it’s good if power devices shut down.

Additionally, since many I2C devices are smart, they can issue a SREQ (service request) so the Picaxe does not have to keep polling a lot of I2C drops. Unused SREQs can be used as needed (I use 2 of them for OLED comm & real-time clock pulse on the kayak project).
Also lets hardware/software be shared across Picaxe variants.
Lots of other reasons, but above is major stuff.
Thanks for posting the pdf with pics. Nice rig & great project.
thanks & good morning,

The start of the project with pictures & attachments is on this site (However, they require a login before seeing pics/attachs, but it's free)

I am thinking about just uploading the rest of the project there since they don't have all the size restrictions as on this sight. However, most kayakers are not technical folks, so it wouldn't see much use.
I know that you have it all figured out, but why I2C and not just use serial comms?
good morning,
I2C is to serial comms as a horse is to a car. The I2C is much faster, way more expandable, & offers a lot more options. You could easily put a hundred devices on the I2C bus, but that would be a challenge with serial comms. It's also easy to do circuit boards for I2C devices (a plus for me since I'd rather be fishing).
Attached are the schematics for the Picaxe-20M2 board & joystick DIO board used on this project. As you can see, there ain't a whole of lot of complexity.
Have a fun day!



Senior Member
Great project and terrific documentation! You should post a video of the kayak & controller in use, that would really complete the presentation.


Senior Member
I agree with the others: TERRIFIC and well documented project.
I'm glad that you could merge both your passions into this project.

Like your "mama trees" software strategy. Very intuitive. Shows all the experience accumulated during your working years.

One question; how did you protect the boards against humidity?
For the connectors on my environmentally-exposed projects I've always used some moly-grease (Nyogel 76V) to protect them; with excellent results.


Senior Member
thanks guys,
Yep, “mama trees” is easier to get your head around than “hierarchical procedural structure”. Anyhow, words with over 3 syllables have to be contracted in southern English (i.e. hi-rar-cul pro-see-drul struc-cher).
Haven’t had any problems with moisture or condensation. The battery & drive electronics are in a sealed box with a fan that runs when the drive is turned on. The (Northern Tools) box does not hold heat very well (a good thing), so it all stays dry. The DB connectors slide into each other so no problem there. I did put dessicant packs in the joystick & display cases.
My next step is to add a GPS auto-pilot. It will be a Raspberry Pi Zero project. This should allow the yak to drive itself from waypoint to waypoint & spot-lock at any position on the water. I could do the same thing by adding another Picaxe in the joystick box, but the math would be a pain & no wireless GPS control panel on my Kindle.
The KYK IDC10 bus (described in the yak project) means I simply have to remove the Picaxe-20M2 board & replace it with a Pi board (with a KYK connector & level adapters) when I upgrade. I like the concept of IO hardware being processor independent.
When it gets warm enough to fish at night, I’ll get my buddy to video the orange yak. With the effects running it looks like a UFO halloween pumpkin on the water (comical but good for fishing).
The secret to world peace: Nations’ leaders should be fishing buddies.
thanks guys,

The secret to world peace: Nations’ leaders should be fishing buddies.
Amen, Bro!

The Japanese have a variant; taking a hot bath together.

The Japanese Prime Minister had hinted he would invite Vladimir Putin for a hot bath to discuss the Kuril Islands. Don't know if the meeting ever occurred, but to my knowledge, the Kurils remain solidly Russian.