Compute Operation - NXP Semiconductors MKL27Z128VFM4 Reference Manual

If the requested DMA transfer cannot cause the DMA request
to negate then the device will remain in a higher power state
until the low power mode is fully exited.
An enabled DMA wake-up can cause an aborted entry into the low power mode, if the
DMA request asserts during the stop mode entry sequence (or reentry if the request
asserts during a DMA wakeup) and can cause the SMC to assert its Stop Abort flag. Once
the DMA wake-up completes, entry into the low power mode will restart.
An interrupt that occurs during a DMA wake-up will cause an immediate exit from the
low power mode (this is optional for Compute Operation) without impacting the DMA
transfer.
A DMA wake-up can be generated by either a synchronous DMA request or an
asynchronous DMA request. Not all peripherals can generate an asynchronous DMA
request in stop modes, although in general if a peripheral can generate synchronous DMA
requests and also supports asynchronous interrupts in stop modes, then it can generate an
asynchronous DMA request.

7.2.3 Compute Operation

Compute Operation is an execution or compute-only mode of operation that keeps the
CPU enabled with full access to the SRAM and Flash read port, but places all other bus
masters and bus slaves into their stop mode. Compute Operation can be enabled in either
Run mode or VLP Run mode.
Do not enter any Stop mode without first exiting Compute
Operation.
Because Compute Operation reuses the Stop mode logic (including the staged entry with
bus masters disabled before bus slaves), any bus master or bus slave that can remain
functional in Stop mode also remains functional in Compute Operation, including
generation of asynchronous interrupts and DMA requests. When enabling Compute
Operation in Run mode, module functionality for bus masters and slaves is the equivalent
of STOP mode. When enabling Compute Operation in VLP Run mode, module
functionality for bus masters and slaves is the equivalent of VLPS mode. The MCG,
PMC, SRAM, and Flash read port are not affected by Compute Operation, although the
Flash register interface is disabled.
Freescale Semiconductor, Inc.
NOTE
NOTE
KL27 Sub-Family Reference Manual , Rev. 5, 01/2016
Chapter 7 Power Management
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