Dave,
I tried changing the LSBPRE to LSBPOST as you suggested, but it seemed to make things worse. I changed DEFINE SHIFT_PAUSEUS to 1 and it seemed to make things the closest to the 8MHz Micro as possible (Looking at the timing on a logic analyzer). I can get temp readings, but they are not always reliable. I should also note that the DS1620s are on the end of a cable about 15' from where the micro is. The temp readings seem to be a little low (reading 58F where it should be closer to 69F, however when I try LSBPOST the reading drops in the 40's (Must be dropping a bit or something). Maybe the 18F46k22 can't handle the cable length as the 18F4620 did so well for all these years.
I will keep it running for a while and monitor the results.

Thanks for your help
Jim


Quote Originally Posted by Dave View Post
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?