Special Programming for “Cascaded” Satellite System Configurations

9.6Special Programming for “Cascaded” Satellite System Configurations

In a 3-tier cascaded satellite system, it is highly recommended for the system design to have more trunks lines between the intermediate master/satellite system and the 3rd level satellite system than there are between the top level master system and the intermediate system. In systems where this is not the case, it is likely that operators at top level master and the intermediate master/satellite will end up fighting for trunk lines coming from the 3rd level satellite system.

There are two user configuration options available (starting in CPU firmware ver- sion 8.70) to eliminate or at least significantly reduce conflicts between operators when this type of system is being used.

Option 1: Using Factory default settings, previously selected satellite cameras remain on trunk lines even after the operator switches back to a local camera view. Although this mode of operation is more desirable in standard systems because it minimizes delays when previous satellite cameras are reselected, it is not advanta- geous to use in cascaded systems. In cascaded systems, all available trunk lines com- ing from the 3rd level satellite system may become used up, making them unavailable to the operators at the intermediate system.

In this situation, keyboard User Function 41 should be set to the NO REM CAM CACHE option at the master site location. In this mode, after the top level operator selects a locally connected camera, the trunk line between the top level and the intermediate level system will immediately be reset to its Start-up camera (as defined in the Monitor Table of the LTC 8059/00 MCS). This action frees the trunk line between the intermediate level system and the 3rd level system so it will be available if needed by an operator at the intermediate level system.

For the monitors being used as trunk lines in the intermediate system, it is important for the “Start-up” camera numbers listed in the Monitor Table of the LTC 8059/00 software to be programmed to specify cameras connected locally or a local unused input (i.e., the raster generator will be displayed when called up). This action ensures that no trunk line is used when a monitor switches to the Start-up camera.

Option 2: If the top level master system and intermediate level system in a cascade configuration can or will be set to operate as “Dual Master” systems, a priority based satellite camera feature can be configured.

In default cascaded satellite system configurations, satellite switching commands are not associated with a user priority level. When a switching command sent from a master site is received by a satellite, the switch selection can immediately be overrid- den by operators at the satellite location who have any priority level. This situation is more likely to be encountered in 3-tier Satellite systems that do not have a good distribution of trunk lines (i.e., more between the top level system and the interme- diate level system than there are between the intermediate system and the 3rd tier satellite).

Since dual master configurations support bi-directional communications, it is possi- ble to set keyboard User Function 41 to use the SAT nnn PRIORITY option for both the top level and intermediate level master systems. The satellite number assigned to the system that is currently being programmed must be specified here. This fea- ture will enable use of the operator’s user priority to determine if access to a desired satellite camera is provided or not. For instance, if no trunk lines are available and

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Bosch Appliances 8500, LTC instruction manual