The DISPC supports no-idle mode, force-idle mode, and smart-idle mode. The mode can be selected by programming the appropriate value in the DISPC_SYSCONFIG[4:3] SIDLEMODE bit field.
Condition of assertion of the SIdleAck signal:
- In no-idle mode: SIdleAck is never asserted.
- In force-idle mode: SIdleAck is asserted unconditionally with a 1-configuration port interface clock cycle delay with respect to an IdleReq assertion.
Note: The proper use of force-idle mode assumes that no interrupt needs to be generated.
- In smart-idle mode: SIdleAck is asserted when at least the following conditions are satisfied:
- No interrupt is pending.
- The DISPC no longer uses the interface clock for the slave port.
Once SIdleAck is asserted, the DISPC interface lock used by the slave port can be shut down at any time.
The conditions of deassertion of the SIdleAck signal are:
- In force-idle mode: SIdleAck is deasserted with a 1-configuration port interface clock cycle delay with respect to an IdleReq deassertion.
- In smart-idle mode: SIdleAck is deasserted with a 1-configuration port interface clock cycle delay with respect to an IdleReq deassertion.
Once SIdleAck is released, the DISPC is fully operational and a DMA request can be processed normally.