Hi, I've been working on some 12c routines to communicate with a DS1621 temperature sensor. Sadly, I've not gotten the routines to work. The assembler file and schematic are at: and Short description: I'm trying to use i2c master mode on a PIC16F872 talk to a DS1621 and display the temperature value on a LCD. Things seem to go OK during intialization (I think.) I've attached buffered LED's to the SCL and SDA lines - I'd kill for a logic analyzer right about now. What I see happening from the LEDs is that during the read temperature loop the SDA line goes from high to low and back while SCL stays high. The start condition. This is all I see, SCL never changes levels. Of course persistance of vision causes trouble; really, I'd kill for a LA. The values displayed on the LCD during this time alternate between displaying 10 and 03 (both decimal.) My i2c routines are modeled after those of John Sands' on piclist.com. I'm hoping this is a code problem that someone else can spot. I'm trying to understand this module on the PIC and can't see what is going wrong. Any other comments on my code are welcome. TIA, Matthew -- Matthew Miller SVCC College Bound, Technology Coordinator -- http://www.piclist.com hint: To leave the PICList mailto:piclist-unsubscribe-request@mitvma.mit.edu