ProSoft Technology 5301-MBP-ASCII - Manual (Page 13)

MBP ♦ ProLinx Gateway Functional Overview
Modbus Plus Protocol Manual
ProSoft Technology, Inc. Page 13 of 52
May 12, 2011
1.2.5 Modbus Plus Global Out Access to Database
When the MBP module's Global Output capability is enabled, up to 32 words of
data can be transferred onto the Modbus Plus network by the module. This data,
typically reserved for high-speed data such as for application control data, is
transmitted each time the module receives the network token.
The number of words transferred to the Modbus Plus network is user determined
through the Module Configuration Block. The following flow chart and associated
table describe the flow of data into and out of the module.
1 The Global Output driver reads configuration data from the configuration file.
This data consists of the number of words to be transmitted by the module
each time the module has the token. In addition, timing data on the update
rate for the Global Out transmission is also obtained from the configuration
data.
2 The Global Out data image is updated through the module's output image.
Based on the update rate configured by the user, the Global Out image in the
Modbus Plus chipset will also be updated.
3 The Global Output driver in the Modbus Plus chipset will transmit the Global
Out data each time the token is received by the module.
4 The Global Output driver status is updated in the module's database.
To enable the Global Output Mode, set the Global Output Length parameter to a
value between 1 and 32. To disable this feature, set the parameter to a value of
zero.