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Clarification Of Ev-Bv4 Digital Input And Output Levels


I have read about the digital inputs and outputs and have some questions to clarify my understanding of them:

Am I correct in assuming that the digital I/O pins can be set as inputs and read as either 0V(logic 0) or +5V(logic 1) via EZ-Script. Also can they be set as outputs and the output level set to 0V (logic 0) or +5V (logic 1) via EZ-Script?

The Data Sheet for the EZ-Bv4 suggests that the high level for a TTL output is 3.3V and doesn't show what the low level is. I am assuming it would be 0V. According to the data sheet a logic high (1) would be 3.3V and it doesn't really show what logic 0 is (should be 0V)? Seems output logic 1 level should be 5v?

What is the digital I/O power pin used for and what is its value. Is this used to power the servos only. I have a Lipo Battery powering my adventure robot so I am assuming the digital I/O power pin is at about 7.4 volts?

Thanks much for the clarifications on the I/O pins and how to set and read them via EZ-Script.....Rick B.

Why is the high level for outputting to a port only 3.3V and when inputing a high level is 5V? (5V=1, 0V=1)?


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Hi @rbonari

The ez-bv4 main chip runs on 3.3V so it can only output 3.3V as a logical high. Yes a logical low is 0V. The ez-bv4 digital and analog pins can accept 5V signals in as they are 5V tolerant.

Yes, the digital power rail will output the voltage you put in. It's 7V to 8.4V with your Adventurebot kit. It can be used to power all sorts of devices but it's recommended to use a voltage regulator (ex: 5V regulator) if you aren't using servos as there aren't many electronics that run off raw 7V to 8.4V without regulation.


Thansks for the clarification ! Can the I/O pins be set and read via EZ-Script? I would assume so. Thanks again...Rick


Yep, for sure! Just use Set [ex: Set(D2, OFF)] and GetDigital [ex: GetDigital(D2)] commands.


Thanks much Jeremie ! Rick



Yes, Jeremie answered my question. Very awesome. In the post above for some reason when I click the down arrow in the box and select Jeremie and then select done it doesn't change what is in the box from unresolved to Jeremie. Not sure why this is. I have noticed this in the past with my Samsung Galaxy S4 when using the ez-robot site (forums).Also, the above " was your question answered" box is the first time I have seen this query in any previous threads....Rick B.


This is because you also have to submit the response. The done option on android devices is misleading - this is because the done option merely means "you're done selecting an option". It does not mean "submit".

This is html web behavior and not unique to ezrobot website.

So, create your post... Such as "thanks Jeremie for your help it's really nice blah blah". Then, select Jeremie from the drop down. Finally, press the reply button to save/submit the form.


Thanks much Jeremie for your help ! Awesome job ! Rick


Hello DJ,

Thanks for the clarification ! I did what you said. Selected jeremie in the drop down and selected done. After this I typed message to jeremie & selected post. Hope it worked....Rick


You're welcome Rick:)


It didn't work:) But i have no doubt that you will figure it out


Hello DJ,

That is odd as I received a thank you from Jeremie. He must have been on the forum at the dame time I made the post......Rick



Had to go my laptop to resolve the issue. Still looking into why this doesn't work on my Samsung Galaxy S4. Will post when I have the answer, but for now I have a work around....Rick B.