Reflective Memory: Point Configuration
Once your devices are configured, you m ay configure points for them.
The fields in the Point Properties dialog box have configuration values that are unique to the Reflective Memory device communications.
1 | Enter general information for a reflective memory point. |
2 | Enter device information for a reflective memory point. |
- Enter General Information for a Reflective Memory Point
On the General tab in the Point Properties dial box, you can select whether the points are read only or read/write.
Important: :
With the reflective memory device communication interface, it is recommended that multiple devices do not have write access to the same mapped memory in reflective memory without implementing an application level scheme to synchronize the writes and prevent concurrent or nearly concurrent updates.
- Enter Device Information for a Reflective Memory Point
Fields on the Device tab in the Point Properties dialog box are as follows.
Field | Description | ||
Update criteria | This device communication interface only supports polled update criteria. When polling is performed, the frequency of data collection is based on the port’s configured scan rate multiplied by the point’s configured scan rate. | ||
Update Criteria | Definition | ||
On Change | Update the point value if the most recently read value is different than the current point value. Note that if an analog deadband is configured, the value read must differ by an amount greater than the configured analog deadband before the point value will be updated. | ||
On Demand On Scan | When an application is requesting the data, and the value is read is collected, the point value is updated. | ||
On Demand On Change | When an application is requesting data and the value read is different than the current point value, then the point value is updated. If an analog deadband is configured, the value read must differ by an amount greater than the configured analog deadband before the point value will be updated. | ||
Address | The specification of the address is based on the model selected and the domain configuration configured by the Reflective Memory DEVCOM Configuration Tool. For a project that used the default domain configuration the valid address range would be as follows: | ||
Address Format | Numeric Range | Native format | |
Qn | 1 – 8192 | Byte (Little Endian) | |
Rn | 1 – 4096 | Word (Little Endian) | |
Poll After Set | Select this only if there is a need to read the value from the device at a rate greater than the actual poll rate. |