AN3259

Software description

Doc ID 17835 Rev 1

9/25

4

Software description

4.1

STM8S peripherals used by the application

This application example uses the STM8S standard firmware library to control general

purpose functions. It makes use of the following STM8S peripherals:

UART2

UART2 is used to communicate with the terminal window running on the PC. It must be

configured as follows:

●

Baud rate = 9600 baud

●

Word length = 8 bits

●

One stop bit

●

No parity

●

Receive and transmit enabled

●

UART2 clock disabled

The communications are managed by polling each receive and transmit operation.

Note:

The terminal window and the STM8S UART peripheral must be configured with the same

baud rate, word length, number of stop bits, and parity.

Timer 3 (TIM3)

TIM3 timer is configured as a timebase with interrupt enabled to control LD1 blinking speed.

GPIOs

The GPIOs are used to interface the MCU with external hardware. Port PD0 is configured as

output push-pull low to drive LD1.

BEEPER

To drive the buzzer, the BEEPER peripheral outputs a signal of 1, 2, or 4 KHz on the BEEP

output pin.

4.2

Configuring STM8S standard firmware library

The stm8s_conf.h file of the STM8S standard firmware library allows to configure the library

by enabling the peripheral functions used by the application.

The following define statements must be present:

#define _GPIO 1

enables the GPIOs

#define _TIM3 1

enables TIM3

#define _BEEPER 1

enables the BEEPER

#define _UART2 1

enables UART2