Re: [Gumstix-users] TTL and RS232

[Dave H. <dhy...@gm...>]

Hi Jay,

>         So, I should be able to connect a unit such as this:
> http://www.sparkfun.com/commerce/product_info.php?products_id=3D465
>
> It uses TTL output, I just need to make sure ground, TX and RX are connec=
ted,
> feed it power via VIN and it should show up as a serial device in the OS?

All of the serial ports show up all of the time, regardless of the
type of connector, logic levels, etc.

This particular device (a GPS) uses 2.85v logic levels. So it really
depends on which boards you want to connect to it.

Connecting to 3.3v should be fine, although I'd use 100 ohm inline
resistors to provide a bit of protection. For something like the
robostix, which uses 5v logic levels, you'll need some type of voltage
conversion chip.

> Many thanks for the clarification, and sorry for the newbie questions :)

We were all newbies sometime :)

--
Dave Hylands
Vancouver, BC, Canada
http://www.DaveHylands.com/