Hardware Manual: emSTAMP- emSBC-Argon (Rev1)
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6.10.2
Wake-up Button S1
The push-button S1 is directly connected with the active-low input PONKEY# of the PMIC (Power-
Management-IC) on the emSTAMP-Argon module.
The pressed button S1pulls the signal PONKEY# low.
This generates a SYS_WKUP signal at PA0 of the STM32MP157.
Wakes up the PMIC from any low-power mode.
6.11
Boot configuration DIP-Switch
The DIP-switch SW1 is used to set the boot mode of the emSTAMP-Argon module. The BOOT[2:0]
configuration pins are connected to SW1.
If a switch is in position “ON”, the corresponding pin is read as “0”.
If a switch is in position “OFF”, the corresponding pin is read as “1”.
The following table describes the available boot mode options:
SW1-3
SW1-2
SW1-1
Initial boot mode
ON
ON
ON
UART and USB
ON
ON
OFF
QUADSPI NOR-Flash
ON
OFF
ON
eMMC on SDMMC2
OFF
ON
OFF
SD-Card on SDMMC1
OFF
OFF
ON
UART and USB
Note: Switch SW1-4 is not connected.
6.12
Battery holder
A battery holder J11 for CR1225 lithium coin cell is available to supply the VBAT power domain of
the emSTAMP-Argon module. The VBAT power domain contains the RTC, backup registers,
retention RAM and the backup SRAM of the STM32MP157 processor.
The battery holder J11 is connected via a 1k-resistor and a reverse-current-protection-diode to the
VBAT-pin of the emSTAMP-Argon module:
Module Pin
CPU Pin Name
Signal
Direction
(module view )
Termination
6
VBAT
V
BAT
Power input
