Jim, Looking at the data sheet, I would change the "SHIFTIN TDAT, TCLK, LSBPRE, [tempIn\9]" statement to "SHIFTIN TDAT, TCLK, LSBPOST, [tempIn\9]" According to the data sheet, the data is valid until the next rising edge of the clock. Also, it takes 750 Milliseconds for each new conversion to complete. I am assuming that your TRS1 and TRS2 port bits are connected to the respective NOT RESET lines on the DS1620's?