Understanding Download By List

This application allows you to create a list of RealTime database (RTDB) points to download to the Remote Terminal Unit (RTU).

The protocol driver attempts to write the list to the RTU with a single protocol message based on RTU protocol capabilities. If the protocol cannot write all the points with one message, it automatically sends multiple messages to write all points. The following drivers support the Download List command:

• Bristol Standard Asynchronous Protocol (BSAP) Driver with CGL for OASyS

• Fisher Remote Operations Controller (ROC)/Fisher Remote Operations Controller (ROC) Plus Driver with Configurable Gas Load (CGL) for OASyS

• Extended Modbus (Xmodbus) Protocol Driver for OASyS

The interface allows you to configure up to twenty lists per remote, with each list capable of holding a maximum of 200 RTDB points.

For download list points with an analog.<name>.curval or a rate.<name>.curate as a source, the protocol driver supports the same analog data types as it supports for setpoint commands.

Note: The Fisher ROC/ROC Plus CGL Protocol only supports the analog data type.

For download list points with a status.<name>.cursta as a source, the protocol driver supports writing both one-bit and two-bit status points. The writing of bit values to the RTU is based on the cursta value.

The steps involved to download a list of points to the RTU are as follows:

1. Create a dnlist record

2. Attach the dnlist record to a remote record

3. Download the list either manually or automatically. For the automatic download to be successful, you will have to create a remdnlistjoin record.