Noob to Arduino and TTL

Hello everyone

I´m a complete noob to arduino, electronics, etc, but not to programming.

I decide to buy an arduino board to try just for fun.

However I noticed that it have many applications.

I don´t understand much of electronics, but I want to use arduino to send events to a gps positioning equipment.

The gps accepts 5 v TTL > 1 msec with at least 7 ma.

I would like to know if I can connect directly the cables from the output pins (to a DB9 male plug, since the gps input port it´s DB9 female) without having to make a circuit with other components.

I have the following desription in the gps manual:

** Event 1 In and Event 2 In are optically isolated digital inputs.
** Inputs (and their return lines) are not referenced and are independent of
internal mPOS power supplies and GND.
** Inputs can be controlled from an external 5V TTL-level source capable of
supplying a minimum of 7 mA of sourcing or sinking current.
** Examples of possible configurations of Event 1 and Event 2 inputs are
shown below.

The images of the examples are in the reply:

Tks to everyone


Here´s the example


Yes it looks like you can directly connect them together. The arduino can drive an opto directly.

Tks for your reply grumpy_mike

Ok, I hope not to blow up anything, it´s a very expensive equipment.

Can I use a simple program like the "Hello world" to blink a led (with some time delay changes) and connect "GPS Event 1 IN" to Arduino pin 13 and "GPS Event 1 Return" to Arduino GND?


Yes that will give you control over that pin so you can generate a pulse. That is if a simple pulse is all that is needed for an event. Do you know how long the pulse has to be?

The pulse has to be longer than 1 msec, the instructions don´t indicate the lenght. I will try with with several lenght´s > 1 msec and see if the gps logs the events.