Romilly's HART® and Fieldbus Message Board

[ Follow Ups ] [ Post Followup ] [ Back to top of Message Board ]

HART physical layer

Message posted by Christian Kolonko (christian.kolonko@gmx.de : 195.4.191.98) on 06 January 2003 at 10:41:05.

Hello,
I'm a student of electronic engineering. I'm working on a project to build a HART "soft modem" using a microcontroller.

Studying the HART specs. (especially the physical link layer) i stumble about following:

... whithin a character, the bit timing is defined by the baud rate. Normally there may be any amount of idle time (at the logical 1 level) between characters, however, HART requires that idle time not exceed 1 byte time. ...

does "logical 1" mean that the carrier of 1200Hz is still there or a "high Level"?
I can't find detailed information about this.

Does anoybody have information about this?
Best regards

Christian Kolonko



Follow Ups:



Post a Followup

Name:
E-Mail:

Subject:

Comments:

[ Follow Ups ] [ Post Followup ] [ Back to top of Message Board ]