Sharp UP-3500 Master declaration, Flow of a master declaration at the back-upmaster

2. Master declaration

When the master or back-up master breaks down, the master declaration procedure should be taken to inform satellites of the breakdown.

(1) When the master breaks down – Master declaration at the back-up master

Flow of a master declaration at the back-up master

Master Back-up master

2) Master declaration operation

	Satellite
1) Detection of a breakdown	3) Updated data
(Transmission stops.)	4) Acknowledgment signal
	Master declaration

1)A satellite detects a breakdown of the master through the system retry function when sending updated GLU data (and clerk data*) to the master. At this point, the message “MASTER DOWN” appears in the pop-up window of the display of the satellite.

(For the system retry function, see pages 55–56.)

2)The master declaration operation must be done at the back-up master. This operation informs all the satellites that the master has broken down and the back-up master will serve as the master hereafter. (During this process, any other operation cannot be done at each satellite.)

3)Each satellite in the IRC system starts sending updated GLU data (and clerk data*) only to the back-up master.

4)The back-up master receives the data and sends back an acknowledgment signal to the satellites.

*Only for the centralized clerk file system

The master declaration procedure is as follows:

1. Enter the PGM2 mode from the mode selection window.

2. Select “7 DECLARE & RECOVERY MA/BMA” from the displayed menu. The DECLARE & RECOVERY MA/BMA window will appear.

3. Select “1 DECLARE MASTER&STOP DB UPDATE.”

NOTE While the master is down, the back-up master performs T-LOG polling as well.

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