Let's Make Robots!

Everyone else is doing it HC-SR04

Ok, Ok... You convinced me! I broke down and bought a few of these El Cheapo SRF05 knock-offs (HC-SR04). It was Jax saying he got his working that put me over the top. Now the real question is  --is there any way to convert this 4-pin set-up to a 3-pin set-up? Currently, trigger and echo are on different pins, is there any way to connect them? I figure diodes would be in order, but for the life of me, and after a bunch of sketches, I can't seem to figure it out. Thoughts?

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i realised its not a srf05

I got mine from eBay china seller and it works great. The four pins did throw me off for a sec considering I only see the three pin type in lots of projects. No problems with arduino so far. Have set it up to test only have not added it to my bot yet. Also all the cheap servos I got on eBay from china worked great no worries 4 out of 4 gonna make a bigger order in the new year.

Well, I slept on it and I am starting to think I may just need to get over this one. I am a bit of a 3-pin purist, possibly a 3-pin snob, and I should just get over myself here and deal with a 4-pin unit. This all goes back to my car stereo days when I used to compete --spaghetti was about the worst thing you could have when the judges were looking. I have been pretty addicted to the Pololu servo-style connectors and pre-crimped wires, I think I may need to just KISS and simply make myself a tidy little wiring harness instead of all this conversion business. This is probably just a forrest/trees moment.

I will say this though, it is great to hear that folks have had some success with these little guys. It is a real toss-up sometimes with knock-offs of this kind.


Yeah the four pins threw me way off for a day. Major headache then success. As long as those trees were green no worries.