Operating phases

Offline

After power-on, the AS-i master goes into offline mode, i.e. there is no communication with the AS-i slaves.

During normal operation, the AS-i master can be put into offline mode (OFFLINE-flag is set) via the process data. The output data of all activated AS-i slaves are set to default value 1_bin, and the input data of all activated AS-i slaves are set to default value 0_bin. The AS-i master is then in offline mode and will send no further AS-i commands.

Start-up

Detection phase

During the detection phase, the I/O ID and ID codes of all AS-i slaves are queried and entered in parameters
- 0x9pp0:20, 0x9pp0:25 (I/O IDs read) or
- 0x9pp0:21, 0x9pp0:26 (ID codes read),
- 0x9pp0:22, 0x9pp0:27 (Extended ID codes 1 read) and
- 0x9pp0:23, 0x9pp0:28 (Extended ID codes 2 read).

All AS-i slaves found are entered in the List of Detected AS-i Slaves (LDS), index 0xF101. The AS-i master will only enter the activation phase once at least one slave was detected or found.

Activation phase

In protected mode the AS-i master activates only the projected AS-i Slaves from the List of Projected Slaves (LPS, index 0xF103).

In configuration mode, all AS-i slaves that were found during the detection phase are activated. To this end the AS-i master sends a parameterization call (activation parameter, 0x8pp0:24, 0x8pp0:29) and a data call (with the default values 1_bin as outputs). All activated slaves are entered in the List of Activated Slaves (LAS, index F102). Once all AS-i slaves have been processed, the AS-i master automatically enters the data exchange phase.

Normal operation

Data exchange phase

During the data exchange phase, the AS-i master exchanges data with each activated AS-i slave. If an AS-i slave does not respond in three consecutive data exchange phases, it is removed from the LAS and the LDS, and its inputs are set to the default value 0_bin. Once a data cycle has been completed with all activated AS-i slaves, the AS-i master enters the management phase.

Management phase

During the management phase, an AS-i command is sent if an operating address is to be set via automatic address programming, or if an AS-i command was requested via the AS-i command interface (index 0x2000 ). Otherwise the AS-i master enters the inclusion phase without issuing an AS-i command.

Inclusion phase

During the inclusion phase, only one command is sent. The system will attempt to find and activate new AS-i slaves, and the respective status is updated accordingly. The steps are the same as during the recognition or activation phase, except that they are now distributed over up to seven cycles.