摘要 |
Circuits, methods, and apparatus that provide transactions to wake an external device from a low-power state before a data transfer. This prevents an interruption that would be caused if the external device exited the low-power state during the data transfer. One example monitors a need for data by a first device. At a predetermined time before data is needed, the first device sends a transaction to a second device. The transaction is intended to wake the second device from a low-power state. If the first device has information to indicate that the second device is not in a low-power state, this transaction can be skipped. The first device then requests data. Later transactions to the second device do not result in the second device exiting the low-power state and therefore do not interrupt or cause delays in the data transfer. |