Sorry - messed up the subject of this on my last post - please forgive... Hi All, I've been trying to get a PIC talking to a Trimble Lassen SQ GPS module (3.3v) with no success so far. Without flaming me for being an idiot , can anyone tell me by reading the below excerpt from the Lassen manual whether or not I need to do anything to the signal before feeding into my PIC? Note again that the Lassen is a 3.3v device. The manual says re the serial interface: As an embedded design, the Lassen SQ GPS provides direct CMOS compatible TTL level serial I/O. The RX and TX signals on the J2 I/O connector are driven directly by the UART on the Lassen SQ GPS. Interfacing these signals directly to a UART in your application circuitry provides direct serial communication without the complication of RS-232 or RS-422 line drivers. Note - The serial I/O signals on J2 are TTL level. They are not inverted or driven to RS-232 levels. Thanks! -- http://www.piclist.com hint: The PICList is archived three different ways. See http://www.piclist.com/#archives for details.