SAM4CM Series [DATASHEET]
Atmel-11203C-ATARM-SAM4CM32-SAM4CM16-SAM4CM8-Datasheet_06-Oct-14
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10.
System Controller
The System Controller comprises a set of peripherals. It handles key elements of the system, such as power,
resets, clocks, time, interrupts, watchdog, reinforced safety watchdog, etc.
10.1
System Controller and Peripheral Mapping
Refer to
Section 7-2 “SAM4CM16/8 Memory Mapping of CODE and SRAM Area”
.
All the peripherals are in the bit band region and are mapped in the bit band alias region.
10.2
Power Supply Monitoring
The SAM4CM embeds Supply Monitor, Power-on-Reset and Brownout detectors for power supplies monitoring
allowing to warn and/or reset the chip.
10.2.1 Power-on-Reset on VDDCORE
The Power-on reset monitors VDDCORE. It is always activated and monitors voltage at start-up but also during
power-down. If VDDCORE goes below the threshold voltage, the entire chip (except VDDBU domain) is reset. For
more information, refer to the “Electrical Characteristics” section of the product datasheet.
10.2.2 Brownout Detector on VDDCORE
The Brownout Detector monitors VDDCORE. It is active by default. It can be deactivated by software through the
Supply Controller (SUPC_MR).
If VDDCORE goes below the threshold voltage, the reset of the core is asserted.
10.2.3 Power-on Reset on VDDIO
The Power-on reset monitors VDDIO. It is always activated and monitors voltage at start-up but also during power-
down. If VDDIO goes below the threshold voltage, the IOs are reset but the core continues to run. Voltage
detection is fixed.
10.2.4 Supply Monitor on VDDIO
The supply monitor on VDDIO is fully programmable with 16 steps for the threshold (between 1.6V to 3.4V). It
provides the user the flexibility to set a voltage level detection higher then the power-on-reset on VDDIO. Either a
reset or an interrupt can be generated upon detection. It can be activated by software and it is controlled by the
Supply Controller (SUPC). A sample mode is possible. It divides the supply monitor power consumption by a factor
of up to 2048.
The supply monitor is used as “system alert” in case VDDIO supply is falling. It can be used while the device is in
Backup mode to wake up the device if VDDIO is falling.
10.2.5 Power-on Reset and Brownout Detector on VDDBU
The Power-on reset monitors VDDBU. It is active by default and monitors voltage at start-up but also during
power-down. It can be deactivated by software through the Supply Controller (SUPC_MR). If VDDBU goes below
the threshold voltage, the entire chip is reset.
10.2.6 Power-on Reset on EMAFE Internal VDDIO
The EMAFE Power-on reset monitors VDDIO. It is always activated and monitors voltage at start-up but also
during power-down. If VDDIO goes below the threshold voltage, EMAFE registers are reset and the EMAFE
regulator is shut down. Note that this POR does not reset the rest of the product. Only the EMAFE related registers
are reset.