Descriptions of the buffers are as follows:

• Scratch Buffers: Each device is associated with 256 Scratch buffers, which exchange information between transactions defined for a device. The data stored in a Scratch buffer will exist as long as the OPC server project is running (or until the Scratch buffer is overwritten in a transaction).
• Rolling Buffers: Each device is associated with one Rolling buffer, which exchanges information between transactions defined for a device. Rolling buffers are similar to Scratch buffers, but differ in that writes append data instead of replacing it. Data stored in a Rolling buffer will exist as long as the OPC server project is running (or until the Rolling buffer is overwritten in a transaction).
• Global Buffers: There are 256 Global buffers, which exchange information among devices. Each Global buffer is associated with all devices under every channel.

Note: Data cannot be copied to Scratch or Rolling buffers associated with different devices.