AN3269

Software description

Doc ID 17904 Rev 1

11/19

2

Software description

2.1

STM8L peripherals used by the application

This application example uses the following STM8L peripherals with the settings described

below:

ADC

current.

●

ADC resolution: 12-bit

●

ADC conversion mode: single

●

ADC sampling time: 9 cycles

TIM4

TIM4 is used to generating the delays needed for display or wait loops.

GPIOs

Port C and Port E are connected to the USER push-button and the LEDs.

●

PC1 set as an input floating pin with interrupt (USER push-button)

●

PC7 and PE7 set as an output push-pull pin (LD4 and LD3 LEDs respectively)

●

edge

●

During the low power modes, I/Os are placed in output push-pull to reduce power

measurement pin, PE6 LP WakeUp pin and PC4)

●

All Schmitt triggers on standard I/O pins are disabled to reduce power consumption

●

The Schmitt trigger on PF0 is disabled in order to avoid measurement errors

LCD controller

The different functions available in the firmware library for LCD are used to initialize, clear,

display strings and scrolling messages needed in the application code. For some low power

mode measurements, the LCD controller is turned OFF to minimize the current consumption

of STM8L152.

Clock

The HSI (high speed internal) 16 MHz oscillator is selected as clock source. The application

manages the peripheral clocks depending on the selected power saving mode. When the

device enters low power run mode, HSI is switched OFF and LSI acts as the main clock

source until the device is woken-up by an external event. When exiting Low power run

mode, the device switches the HSI oscillator back ON. On the other hand, LSE is switched

ON during Manufacturing test mode (see Section 1.5.3).

2.2

STM8L15x standard firmware library configuration

The stm8l15x_conf.h file of the STM8L standard firmware library allows you to configure the

library by enabling the peripheral functions used by the application.