BASIC- first steps use: Sparkfun OpenLog

I've been meaning to get going with the Sparkfun OpenLog device for years.

Seems a great device.

As I understood it, you hang it on a serial line, send stuff, and it records that stuff to an SD card.

From official wiki, Home · sparkfun/OpenLog Wiki · GitHub

[If you just want to use it...]

"Just power up OpenLog and by default (in v1.1 and above) OpenLog will log any serial text thrown at it. No commands, no configuration required. Just power up and go!"

Umm. Well. Any GETTING STARTED with SIMPLE USE guides out there?

The beast is capable of a whole slew of neat things, but there's so much about them on the documentation pages (Sparkfun and Wiki) that if SIMPLE use is explained, I've not found it.

I don't want to connect it to my Arduino where I would connect the programming cable. Swap back and forth endlessly during app development? So! I can read! Vcc, GND, Rx, TX... fine... I can connect those. WHY DO I WANT TO CONNECT DTR and something to the OpenLog's output, "TX0"?

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The previous OpenLog (DEV-09530) could accept a 5v data signal. The current one (DEV-13712) speaks only of tolerating 3v3. Is it really ONLY 3v3 tolerant... or did they just forget to mention that 5v was acceptable? Can't wait to get going with this... Thanks for any help!

I haven't used one, but I can help with one of your worries, I saw this somewhere on the Sparkfun page:

VCC Input: 3.3V-12V (Recommended 3.3V-5V)