Configuration Manual Owner manual

Publication 1757-PM002A-EN-E - June 2006

Basic Function Blocks 3-7

• QUB: Queued User-triggered Bidirectional

The quantity of each class of VCR that is available for configuration and

communication is device dependent. The quantities are specified in the DD

files, which are provided with each device. An example of the quantities

defined in a DD file, specifically the *.cff file, is shown below.

As can be seen, the quantities are broken into sub-categories depending on

usage. The above example states that the device can have more publisher BNU

than subscriber BNU. Additionally, the device has no client QUB VCR, but it

has the ability to serve 8 server QUB VCR. Currently, these limits manifest

themselves in either download or communication errors when they are

exceeded.

There is also a nuance to the quantities that need to be emphasized with regard

to linking devices. The 1757-FFLD *.cff file is used below as an example.

Table 3.1 : VCR Classes

BNU QUU QUB

Permitted Roles Publisher, Subscriber Source, Sink Client, Server, Peer

Conveyance Paths 1 1 2

Conveyance Policy Buffered Queued Queued

Transmission Policy Network Scheduled User Triggered User Triggered

// From VcrListCharacterisitcs

MaxEntries = 44

NumPermanentEntries = 44

DynamicsSupportedFlag = FALSE //Rev 1.5

StatisticsSupported = 0x0 //Rev 1.5

MaximumNumberOfClientVcrs = 0

MaximumNumberOfServerVcrs = 5

MaximumNumberOfSourceVcrs = 8

MaximumNumberOfSinkVcrs = 0

MaximumNumberOfPublisherVcrs = 19