stm32samples/F0-nolib/Servo

Servo motors SG-90 management

GPIO

• PA0 - (ADC_IN0) - Servo1 control,
• PA1 - (ADC_IN1) - Servo2 control,
• PA2 - (ADC_IN2) - Servo3 control,
• PA3 - (ADC_IN3) - external analogue signal,
• PA4 - (PullUp in) - ext. input 0,
• PA5 - (PullUp in) - ext. input 1,
• PA6 - (TIM3_CH1) - Servo1,
• PA7 - (TIM3_CH2) - Servo2,
• PA9 - (USART_Tx) - TX,
• PA10 - (USART_Rx) - RX,
• PA13 - (PullUp in) - Jumper 0,
• PA14 - (PullUp in) - Jumper 1,
• PB1 - (TIM3_CH4) - Servo3,
• PF0 - (OpenDrain) - Buzzer,
• PF1 - (OpenDrain) - External LED (or weak laser module).

UART

115200N1, not more than 100ms between data bytes in command. To turn ON human terminal (without timeout) send "####".

Protocol

All commands are in brackets: [ command line ].

'[' clears earlier input; '\n', '\r', ' ', '\t' are ignored. All messages are asynchronous!

Commands

• d - debugging commands:
  • A - get raw ADC values,
  • w - watchdog test;
• R - reset;
• t - get MCU temperature;
• V - get VDD value.

Messages

Servos

The board controls up to three servos like SG-90. Three timer's outputs used for this purpose. Timer frequency 50Hz, pulse width from 500 to 2400us.