emSTAMP Helium (Rev3)
13/23
5.7
Analog to Digital Converter
The emSTAMP-Helium module can perform analog to digital conversion on up to 12 Pins.
Tha ADC provides 12-bit Resolution, with Enhanced Mode up to 14 bits. The ADC may also
be used as resistive 4-wire and 5-wire Touchscreen Controller.
The reference voltage for the analog to digital converter should be applied to VDD_ANA pin.
5.8
Status LEDs
A dual-color status LED is placed on the CPU module. The LEDs are connected to the PWM
capable Pins PB6 and PB8 and may be used for custom specific indicators.
5.9
Recovery Pin
The recovery pin may be used to force the software into a recovery state. For details see the
software documentation.
Leave this pin unconnected if not used.
5.10
Base Power Enable Signal
The BASE_PWR_EN signal is used to disable the peripherals on the baseboard while the CPU
is in low power/sleep mode. This signal is low during sleep states and goes high when the
CPU starts up or returns to normal state.
5.11
WAKEUP Signal
The WAKEUP Signal may be used to wake the CPU from power save states. The WAKEUP Pin
has an internal pull-up resistor and should be driven by open drain/collector outputs, or
connected to GND through a switch. If unused, leave this pin open.
5.12
Reset
The module provides a RESETIN# Pin on which an external reset signal may be applied. The
RESETIN# Pin has an internal pull-up resistor and should be driven by open drain/collector
outputs, or connected to GND through a switch. If unused, leave this pin open.
The RESET# Pin of the module provides access to the onboard reset network. It might be
used to reset peripherals on the baseboard while the CPU is also in reset state. The RESET#
signal uses LVTTL level and is active low.
