1 Wire® field network
The 1 Wire® field network
is a standard protocol based on a single wire, as the name indicates,
that includes many devices and sensors frequently used in the
industrial and building automation environments. On the market
actually there are numerous components based on this communication
protocol, that have a very interesting price/oerformance ratio.
This is moreover improved by a simple and cheap connection modality,
infact only three wires are necessary: two for power supply and
the third for the bidirectional communication; on this wires all
the devices can be connected in network modality by chosing the
best physical position.
Among the available devices we can list the following ones:
The 1 Wire® protocol is provided of all the communication tecniques that allow an high transfer rate and a big security on data validity. This is possible thanks to univocal addressing mode, polinomial CRC controls, many check commands and complex management algorithms.
has the knowledge on 1 Wire® protocol management and
it can be applied to each card provided of at least one digital
I/O bidirectional line. This know how has been introduced
in some cards that are so able to manage more lines with this
protocol. These implementation coincide with a firmware that communicates
at high level with the user on one side and that manages the 1
Wire® protocol, thus the devices, on the other side. By
using a list of commands properly developed, the user can easily
communicate with all the available devices by simply transmitting
and receiving the required data and without taking care of timing,
line direction, CRC, conflicts, etc.
The developed commands are:
As described the available commands don't support the high level management of several devices for each line in fact for example it is not implemented the "Search ROM code" command usefull to recognize the ROM codes of the connected devices. A network connection of more 1 Wire® devices can be anyhow managed through the low level developed commands: these can be used first to locate the code of the connected units and then to address and manage them separately.
The management of 1 Wire® protocol is performed by a proper firmware that executes the already described operations; this firmware is supplied as executable code already saved in the card and it is complete of:
The described management firmware is available for the following grifo® cards:
and on specific request it can be implemented also on numerous other cards that have at least one digital I/O bidirectional line. For detailed information please contact directly grifo®.
Page up-dated at September 02, 2008
Home Utility Indice Cat.