3.4.4. Setting up interaction between devices

The run control dialog device interaction tab is shown in Figure 3.16. There can be several tabs of device TAP controller numbers that list all the available devices in blocks of four. The tabs enable you to set up the interaction between single devices or a range of devices.

On tabs containing fewer than four devices, NOT VALID is displayed for the unused boxes and the controls are grayed out.

Figure 3.16. Setting up interaction between devices

Setting up interaction between devices

Each device listed on the tab has a number of control settings:

Range field

This is the drop-down list box directly beneath each of the device descriptions. It enables you to select any devices that are to be stopped by the current device. The default setting is All Devices.

If there are more than two devices available, you can select all devices, individual device numbers, or a range of devices.

For example, if you had 10 devices listed, you can stop devices 2, 5, 7, 8, and 9 using the following notation:

2, 5, 7-9

Disabled

Stop events from this device are disabled and have no control over other devices.

Single

Forces any devices in the range field that are currently running to stop. If any of the devices in the range field are forced to stop in this manner then no stop events for these devices are actioned.

Cascade

Forces any devices in the range field that are currently running to stop. If any of the devices in the range field are forced to stop in this manner then any stop events for these devices are also actioned. If a device is not running and a stop event is actioned for that device, then the stop event is completely ignored.

Note

Stop events do not cascade through processors that are already stopped.

For example, assuming that initially devices one to ten are all running, Figure 3.17 shows that when device 1 stops, three other devices stop. This in turn stops a further set of devices.

Sync. Start

When enabled, this processor is part of the synchronous start group. When one processor is started in the synchronous start group, the processor is marked ready to start. Every processor in the start group starts at the same time when they are all ready to start.

Figure 3.17. Cascade operation

Combining settings

To provide finer control, you can combine settings to achieve individual results. Using the diagram in Figure 3.17 as an example:

  • If device 4 is disabled, devices 5, 7, 9, 10, and 11 are not affected by the control settings from device 1.

  • If devices 4 and 5 are set to Cascade, but device 7 is disabled, the control settings from device 1 reach device 9, but not devices 10 or 11.

  • If device 6 is set to Single instead of Cascade, device 8 is not affected by the control settings from device 1.

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