@Jeremie This is what I think I did with the resistor in the signal line. Is this okay for the ez-b though?

I think adding a diode to the signal line only would work just like the AA circuit I used. The AA battery acted as a diode stopping the voltage coming from the signal pin. The diode would likely do this as well. I just don't know what diode to use, or where to find it. I have a bunch of de-soldered ones I could use, just not sure how to classify them.

@Techno (or should I call you @MHO now?) Adding resistors to the ez-b is always ok, adding resistance only limits the current or pulls a signal high or low by default. Just make sure that if you are pulling an ez-bv4 pin high use the 3.3V supply. Technically you can pull an ez-b I/O pin up to 5V (as the I/O pins on the ez-b are 5V compatible) but we'd recommend 3.3V.

Adding a diode in series with an ez-b I/O pin won't really do much for you besides drop the voltage by ~0.7V (forward voltage drop of the diode). I guess a diode could block any stray voltage from feeding back into the I/O pin but I don't think it's going to help you in this case (unless you are doing your own flyback circuit). If you want to use a diode a couple standards for signal use are 1N914 or 1N4148, for power try the 1N4001-1N4007 series.

I don't think we ever cleared it up but are you creating your own relay control circuitry or are you using a relay board of some sort. If you are using a relay board can you provide a link or a picture?

I think he is using these: https://synthiam.com/Community/Questions/6669

Alan

If the relay is the same in the Post (Alan's link) ...

and following the post, everyone mention the same things (diode, transistor,safe,5v,etc)

and DJ's asks the question:

Quote:

does that have a transistor on the board?

i also wrote:

Quote:

MazeHorizonTech,

Can you post a pick/url of your Relay ?

we can keep writing stuff, probably something will work out

Maze posted some info in the other thread:

1. ebay link:

The picture is not clear what kind of components are presented in the PCB, there are something there besides the relay, so a clear picture from the PCB can help identifying the components.

2. Songle Relay (PDF) That is the relay part, but the PCB does have more than the relay, so the relay per see is a common component does not help.

A good PCB picture exposing the side where is control logic (IN/VCC/GND) will definitely help.

Hmmm.. If you read through that whole thread (which granted, is a year old, so may not not be the relays he is trying to use here) pretty much all the same questions were asked and answered, with the recommendation that it be controlled with a transistor and not directly connected to the EZ-B.

@MHO... Are these the same relays?

Alan

Ill get you guys pictures.

The post @thetechguru linked did mention diodes i believe, but it too suggested making a switch to run a switch.

@Jeremie As long as it isn't hard on the Ez-b I may just run the reverse circuit with the resistor. The diode is exactly that, stopping the flyback voltage, as explained by a previous post, like the AA trigger I made.

The relay circuit has a diode, what appears to be a transistor, and 3 resistors, along with 2 LEDs.

Regarding pull-up (5V) or pull down (0v) resistors connect to a EZB Pin does not change the EZB Pin voltage output.

IF the EZB's pin has 0v and you have a pull up(5V) the result is 0V

If the EZB's pin has 3.3v and you have a pull up (5V) the result is 3.3v

even if the EZB pin has 0.5v (the normal values are 0 or 3.3v) the output will be always the EZB pin no matter what kind of pull up or pull down you have.

pull up/down resistors are used in:

1. open circuits like a push/switch button
2. open collector circuits like I2C, (i2c circuits communicate pulling down (0V) or leaving open the lines)

@Jeremie can you please validate my assumptions ?