Honeywell Touchpoint 4 User Manual

Touchpoint 4 Serial Communication Protocol Issue 1 09/07
Glossary
The following terms are used in this manual:
Handshake: The process of acknowledging a communication has been received.
The Touchpoint4 gas detector controller uses ACK/NAK responses.
Hexadecimal: A type of numbering system with a base of 16. In this numerical system,
thelettersAthroughFrepresentsnumbers10through15respectively.Forexample,
3Finhexadecimalrepresents63indecimal.Theshortenedversionoftheword
hexadecimalisgenerally"Hex",asin"Hex3F.""0x"isthenotationusedinthismanual
forhexadecimal(e.g.0x3F).
Instrument: This term is used to refer to the Touchpoint4 gas detector controller.
Master: A computer or PLC that communicates with slaves using the
Touchpoint4 protocol.
Packet: A block of information that is passed between the master and the slave.
A packet is made from many bytes of information.
Protocol: The manner in which data is transferred and the format used for the transfer.
Touchpoint4 protocol refers to the packets of transferred data the Touchpoint4
instrument recognizes.
Slave: Touchpoint4 gas detector controller. A network may have several slaves.
Time-Out:Themaximumamountoftimeallowedbetweenthetimethelastbyteofa
packetissentfromthe“master”devicetothetimethe“slave”deviceresponds.
The time-out period of 1 second is recommended for this protocol. In fact, the period
fromrequesttransmissiontoresponsereceptionisnotmorethan500ms.
2

Honeywell Touchpoint 4 Specifications

General

Brand	Honeywell
Model	Touchpoint 4
Category	Gas Detectors
Language	English