I have the modul http://www.sparkfun.com/commerce/produc … ts_id=9333 bute I’m not sure how connect to pc.
I was conect pins RX, TX an GND to DB-9
For the alimentation I was connect pins VDD-IN, VDD-BATT on 3.3V and pins GND, 3.3V-RIN on 0V
Is correct for to connect on pc ?
Thanks all
After to connect the modul of PC by DB-9 I see: E‘$i_FFHN³$É‘É’&g“òÒ2R¦æSrRRfK–,]3éi9©¹)Ö and I don’t know how enter the command “$$$” for start setting…who can help me please ?
Who can help me please ?
Please, I need help
Likely you fried the module…due to the fact that a PC generally uses REAL RS-232 voltages (-12v - +12v), whereas that module appears to use 3v levels on the UART pins.
How much did that module cost? Ouch…
Connecting it to a PC without a level converter was surely not the right thing to do.
Thanks for your response, I didn’t know for the voltages UART -12v - +12v 
The UART is not ±12V the RS232 COM port on the computer is ±12V. The UART in the module is expecting 0V & 3.3V logic levels.
Google RS232 to learn about the voltage and logic levels.
It is possible that your module isn’t fried as many newer PCs use lower voltages on the RS232 Com port. But the logic levels are inverted from what a UART expects. This is the other reason why a RS232 level translator is required. Look up the MAX232 chip as this is the most common RS232 level translator IC.
Yes, translator is what I meant vs. ‘level converter’.
On that note, I just checked my desktop and laptop PCs for voltages on the serial port. You’d think I would’ve checked that years ago…
The desktops (one older 2003 model, one newer 2008 model) both had +/- 12v on the serial port.
The laptops (two older 2004 models, three newer 2009+ models). The 2004 models had +/- 12v on the serial port. One of the 2009 models with a serial port barely had 9v on the serial port. The other 2 laptops have a USB/serial converter on them. Both of them were 5v on the converters.
Thanks for they informations, I call my teacher, he will look the problem this afternoon.