Combination Lock


Well-known member

Recently I have been working on a combination lock that uses a picaxe 20x2.

I would like to post a video of it on here, but I can't figure out how.

If someone could tell me I will post the video and a description.

If not, I will post some pictures and a description.

Thank you.


Technical Support
Staff member
I would like to post a video of it on here, but I can't figure out how..
I don't believe you can post video as attachments but it's possible to link to video and media files elsewhere for example -


would be used to point to

which gives -

Details on code tags available at -


Well-known member
I now have a video of the combination lock.

This link takes you to a shared file on, and you should be able to watch it right there. If not, and you still want to watch it, download it.

I can explain the bad sound quality. My camera is really old, and the microphone is probably going out. This might explain the beeping sound. Or it might be morse code interference. I also converted and compressed the original file, and it lost some quality there.

I will post the code soon, maybe this weekend.

file lock 3.PNG romote3.PNG
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Senior Member
Great stuff !.

You only started with PICAXE last November, and now you have this complex project up and running.

I'm sure you will have plenty more projects to show us in the future.




Well-known member
I'm sure you will have plenty more projects to show us in the future.
I'm working on an upgrade to this lock currently, and a secret spy weapon (you will see what it is when I get it done).

Actually, this combination lock has been a work in progress for about two years. I started with buttons that connected a 555 timer to each decade counter. When the right combination was reached, the and gates output high and signalled the 555 timer to stop. When I put the picaxe in, I just took out the buttons, the 555 timer, and added the IR detector.
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Well-known member
Hello, I have my second version of my combination lock.
It was completed almost the same time as the first one, but I havn't got around to posting it until now.
Here is a url for the shared dropbox vidio:

Here is my code for the new lock, and the code for the remote is the same as last time.

I know that the combination lock code could be simplified to use less space, but I had a whole 4 KB of memory to work with!

I also know that I could use less variables, but I used all of them on purpose. In Ron Hackett's book "Picaxe Microcontroller, Projects for the Evil Genius", he stated that he never yet had a project that needed all 56 variables of a picaxe 20X2. I decided to try to come up with a project that could use them all!


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