Hardware Manual: emSTAMP- emSBC-Argon (Rev1)
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5.16
JTAG Debug
For programming and debugging the STM32MP157 offers two interfaces:
Serial Wire Debug (SWD)
JTAG Debug
Both interfaces are available via the same pins on the SMD pads on the bottom side of the module.
Module Pin
CPU Pin Name
Signal
Direction
(module view )
Termination
137
JTCK-SWCLK
JTCK_SWCLK
I
IPD
138
JTMS-SWDIO
JTMS_SWDIO
I
IPU
139
JTDI
JTDI
I
IPU
140
JTDO-TRACESWO
JTDO
O
IPU
141
NJTRST
JTRST#
I
IPU
5.17
Status LEDs
A dual-color (red and green) status LED is placed on the CPU module. The LEDs are connected to
the port pins of CPU via series resistors. The LEDs have a positive logic, i.e. the LEDs are turned on if
the output set to high. The LEDs may be used as custom specific indicators.
Module Pin
CPU Pin Name
Signal
Direction
(module view )
Termination
-
PA13
LED_RED
n.a.
SR 100R
-
PA14
LED_GREEN
n.a.
SR 100R
5.18
User Power-On Key (PONKEY#)
The PONKEY# signal may be used to wake the PMIC (power management IC) from powersave
states (OFF, STOP and STANDBY). The PONKEY# has an internal pull-up resistor in the PMIC and
should be driven by open drain/collector outputs, or connected to GND through a switch. If
unused, leave this pin open.
Module Pin
CPU Pin Name
Signal
Direction
(module view )
Termination
7
-
PONKEY#
I
IPU