16.5.4.1 SRAM Automatic Low-Power Mode
The SRAM is by default put in Low-Power mode (back-biased) if the device is in Standby Sleep mode.
This behavior can be changed by configuring the Back Bias bit in the Standby Configuration register (STDBYCFG.BBIASHS), refer to the table below for details.
Note: In Standby Sleep mode, the SRAM is put in
Low-Power mode by default. This means that the SRAM is back-biased, and the DMAC cannot
access it. The DMAC can only access the SRAM when it is not back biased
(PM.STDBYCFG.BBIASHS=0x0). When the SysTick Overflow Interrupt is enabled the RAM Back Bias
Control must be disabled (PM->STDBYCFG.bit.BBIASHS = 0) before entering Standby sleep
mode.
| STBYCDFG.BBIASHS | SRAM | |
|---|---|---|
| 0x0 | No Back Biasing | SRAM is not back-biased if the device is in Standby Sleep mode. |
| 0x1 | Standby Back Biasing mode | SRAM is back-biased if the device is in Standby Sleep mode. |