The controller spends virtually all of its
time in the Observation state. During the Observation state, status_observation is asserted High and the controller observes the FPGA
configuration system for indication of error conditions, in addition to ECC-based ROM and
auxiliary errors.
If no error exists and the controller receives a command (from either the Command Interface or the Monitor Interface), the controller processes the received command. Only two commands are supported in the Observation state, the Enter Idle and Status Report commands. The controller ignores all other commands.
- Enter Idle
- This command can be applied through either the Command Interface or the Monitor Interface. This is used to idle the controller so that other commands can be performed. This command causes the controller to transition to the Idle state.
- Status Report
- This command provides some diagnostic information, and can be helpful as a mechanism to “ping” the controller. This command is only supported on the Monitor Interface.
In the event an error is detected, the controller reads additional information from the configuration logic in preparation for a correction attempt. After the controller has gathered the available information, it transitions to the Correction state.