Field Device Development

How is Character Time calculated?
Character Time is based on Baud Rate. HART characters consist of 11 bits. For 1200 Baud networks, the character time is as follows:  1200 Baud = ...
Fri, 11 Nov, 2016 at 12:54 PM
Command 6 Notes for Developers
If the HART device receives Command 6 with an invalid Loop Current Mode value, the device MUST NOT change its Polling Address and give a Response Code ...
Wed, 12 Oct, 2016 at 1:44 PM
Where can I find Device Family Commands?
Device Family Commands are discussed in the following documents: Command Summary Specification (SPEC-099, FCG TS20099), sections 6, 7.1, Table 9, 8.3, 8...
Thu, 27 Oct, 2016 at 4:02 PM
Burst mode data refresh
When the Burst Timer countdown reaches zero, the device should burst (publish) the latest available data. The buffer of measurements to burst is refreshed...
Tue, 8 Nov, 2016 at 4:04 PM
What is Burst-Timer?
Burst-Timer(BT) is used by a Burst-Mode HART Device to trigger the transmission of a BACK.  When BT lapses (i.e., reaches 0) a BACK is transmitted.
Tue, 8 Nov, 2016 at 4:10 PM
What is a BACK message?
BACK (Burst Acknowledge) is the HART slave message transmitted to a master without a corresponding master request (i.e., without an STX). BACK messages ...
Tue, 8 Nov, 2016 at 4:26 PM
What is an STX?
A HART transaction consists of an STX and a corresponding ACK. STX is Start of Transaction since it begins the HART transaction. STX is also referred to a...
Tue, 8 Nov, 2016 at 4:16 PM
What is an ACK?
A HART transaction consists of an STX and an ACK. The ACK is the Acknowledge which is also known as the response of a slave device to a master message (i...
Tue, 8 Nov, 2016 at 4:17 PM
When does BACK (Burst mode publish) to each master?
Every time the Burst Timer expires, the bursting slave must send a BACK to a different master. If more than one burst message are configured, then the sam...
Tue, 8 Nov, 2016 at 5:02 PM
When does command 108 change the BACK message?
When in burst mode a BACK must immediately follow every ACK from the burst-mode device.   Command 108 response(ACK) must indicate the new Command nu...
Tue, 8 Nov, 2016 at 5:05 PM