GWY-800-B Features
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Doc No: UMAN\GWY-800-B\0706
REVISION 0
In the above example, number of control bits are 36.
So 36 / 16 = 2 (Number of words in control field)
36%16 = 4 (i.e. Non-zero so add 1 in the number of words in the control field), so number of words in control field are
2+1 = 3. So number of words in the control field should be choosen as 3. For any block any control bit can be
choosen.
Control Word can only be used in Master-Master mode since no continuous data transfer takes place in Master -
Slave mode (data transfer only takes place on Master's request)
When the Control Word is disabled, Block execution is totally controlled by Repeat Cycle settings. When the
Control Word is enabled, Block execution is controlled using discrete bits of that word.
Bit 0 in control word controls execution of Block #1
Bit 1 in control word controls execution of Block #2
:
Bit 15 in control word controls execution of Block #16
When a bit is high, ‘1’, corresponding Block is executed depending on its Repeat Cycle. When a bit is low, ‘0’,
execution of corresponding Block is disabled.
4.4
Error Indication Bit
This feature enables detection of communication breaks during error free communication between Gateway and two
devices. Communication breaks can occur due to no cable connection, wire faults, device power failure at both ends
of Gateway. An Error bit can be designated in each external device connected to
Gateway. Using this bit, fault at the PLC1 end can be reported to PLC2 Device and fault at PLC2 end can be re-
ported to PLC1 Device. When communication error occurs on PLC1, Gateway sets error bit in PLC2 device. Error
Indication Bit can only be used in Master-Master mode. In Master-Slave mode any error can easily be detected by a
communication time out on the Master.
Error indication bit can be enabled using Gateway configuration software. Normally Error bit is disabled for a New
project. It can be enabled just by clicking on the check box in the setup software. Error indication bit can be enabled
in both or any one of the Devices connected to Gateway. Error Indication bit is “OFF” to indicate error free communi-
cation. In case of communication error on PLC2, Gateway sets error bit on PLC1 port and vice versa.
4.5
Communication Parameters
Communication Parameters of Gateway can be set from configuration Software. This enables Gateway to readily
communicate with any device. Communication parameters for PLC1 and PLC2 ports can be configured indepen-
dently. This feature allows changes in Baud rate, Number. of stop bits, Parity etc. at any time without downloading
the driver for that particular device. After the driver for a particular device is downloaded, the communication param-
eters can be changed simply by selecting new communication parameters and downloading the same project.
NOTE:
Default communication parameters for the HART are 1200-8-odd-1. So keep the PLC 2 settings as above.
For the pass through port the communication parameters are fixed. to 1200-8-Odd-1.
