STM32W108CBU6 STMICROELECTRONICS [STMicroelectronics], STM32W108CBU6 Datasheet - Page 131

• Manufacturer Part Number: STM32W108CBU6
• Description: High-performance, IEEE 802.15.4 wireless system-on-chip
• Manufacturer: STMICROELECTRONICS [STMicroelectronics]

STM32W108CB, STM32W108HB
9.1
9.1.1
9.1.2
9.1.3
Functional description
Setup and configuration
To use the ADC follow this procedure, described in more detail in the next sections:
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GPIO usage
A GPIO pin used by the ADC as an input or voltage reference must be configured in analog
mode by writing 0 to its 4-bit field in the proper GPIO_PnCFGH/L register. Note that a GPIO
pin in analog mode cannot be used for any digital functions, and software always reads it as
1.
Table 15.
See
to configure the GPIO pins.
Voltage reference
The ADC voltage reference (VREF), may be internally generated or externally sourced from
PB0. If internally generated, it may optionally be output on PB0.
To use an external reference, an ST system function must be called after reset and after
waking from deep sleep. PB0 must also be configured in analog mode using
GPIO_PBCFGH[3:0]. See the STM32W108 HAL documentation for more information on the
system functions required to use an external reference.
ADC0 input
ADC1 input
ADC2 input
ADC3 input
ADC4 input
ADC5 input
VREF input or output
Analog Signal
Section 6: General-purpose input/outputs on page 46
Configure any GPIO pins to be used by the ADC in analog mode.
Configure the voltage reference (internal or external).
Set the offset and gain values.
Reset the ADC DMA, define the DMA buffer, and start the DMA in the proper transfer
mode.
If interrupts will be used, configure the primary ADC interrupt and specific mask bits.
Write the ADC configuration register to define the inputs, voltage range, sample time,
and start the conversions.
ADC GPIO pin usage
Doc ID 16252 Rev 2
GPIO
PB5
PB6
PB7
PC1
PB0
PA4
PA5
GPIO_PBCFGH[3:0]
GPIO_PBCFGH[7:4]
GPIO_PBCFGH[11:8]
GPIO_PBCFGH[15:12]
GPIO_PCCFGH[7:4]
GPIO_PACFGH[3:0]
GPIO_PACFGH[7:4]
Configuration control
for more information about how
Analog-to-digital converter
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