Hello Werner & other PIC.ers, Could be CCS are having a hard time keeping up at the moment. I've been implementing the ex_pbusm.c routine to hang a bunch of 'F84s onto a one-wire bus, using the B0 pin as serial send/serial receive (receive under isr.). After hours of `after hours' grinding my brain against inscrutable code (for me, anyway) I finally had to swallow my pride & call for help - which they promptly gave me. Turns out there really was a bug or two in the source, and I've now got a revised edition from them. Haven't emerged from `Monday fire-fighting mode' yet to run it. .. To answer your question "can you help with DS1820 routine?", well...... not exactly, er.. but..... please be aware that the CCS routines as published with the docs. aren't necessarily infallible. However, the guys there have not dragged their fingers in coming up with answers, and I thank them for that. Best regards, John .. email from John Sanderson / JS Controls, Boksburg, RSA Manufacturer & purveyor of laboratory force testing apparatus and related products and services. Tel/fax: Johannesburg 893 4154 Cellphone 082 453 4815