SparkFun Forums

[exeng]

Having fried an expensive board (not the WAV Trigger) I'm extremely paranoid and cautious when is comes to matching 3.3v and 5V devices. Yet I see in this example of an Arduino UNO to Wav Trigger serial connection http://robertsonics.com/2015/04/25/ardu ... -tutorial/ that there is no level shifting shown. Is this safe?

I'm about to switch to a 5V based MCU from a 3.3V MCU and the last thing I want or need is a fried WAV Trigger serial port.

[exeng]

Well seeing no replies, just to be safe I'm using a voltage divider on the TX to the WAV Trigger to drop from 5V to 3.3V. Seems to be working just fine.

[robertsonics]

You need to allow a little more time for replies - it's the weekend.

All WAV Trigger inputs, including the serial RX, are 5V tolerant.

[exeng]

You are correct. I should be more patient. My comment was not meant as a reflection on the forum response time. I just want to move on to a new board and to provide an update. I was hoping for a quick response but understand that it doesn't always come as soon as we like.

Thanks for the response and your support. It's good to know that I won't have to worry about the serial connection logic levels when moving from board to board. I recently fried an expensive SAM based board and as result have become hyper sensitive to matching logic levels and using proper power supplies. I love the WAV Trigger and have become very protective of it. Better to safe than sorry.

[yung_landi]

hi, im a complete newb to serial communication, the rx / tx thing.
question: is it possible to use that https://www.arduino.cc/en/uploads/Main/ ... 03-240.jpg device here to update the firmware of my wav trigger ?

"This version of the Mini USB Adapter breaks out many more pins of the FTDI USB-to-serial chip. It is labeled "USB Mini 03".

[exeng]

Call me paranoid but I have a FTDI device that allows me to select 3.3V or 5V output. I suspect that yours is 5V only. That said, Jamie (Robertsonics) said that the WAV Trigger is 5V tolerant on the TX and RX lines.

All WAV Trigger inputs, including the serial RX, are 5V tolerant.

Your FTDI board should work for you.

BTW, I found the firmware update process to be very easy and painless to do. Love the WAV Trigger.

[yung_landi]

Your FTDI board should work for you.

thank you --- so i connect tx->rx and rx->tx, and then GND aswell ?
as far as i understood, there is no power (5V+) connection needed from as far as i power the wav-trigger itself ?
this is the only thing i'm not 100% sure about - the rest is pretty well explained in the user-guide.

[exeng]

You would power the WAV Trigger however you normally power it. The FTDI connections are as you described GND->GND, TX->RX, RX->TX.