Tagged: uvision

L3GD20 3-axis digital gyroscope example 10

Library 28- L3GD20 3-axis digital gyroscope

MEMS sensor L3GD20 is included on STM32F429-Discovery board, so I made a library to use it. This is 3-axis digital gyroscope, so it can measure rotation in X, Y and Z axis. L3GD20 sensor works with SPI communication, or I2C. On Discovery board is connected for SPI mode, SPI5 is used for communication. L3GD20 can be set to work in 3 different full scales: 250, 500 and 2000 dps. Sensor has also possibility to measure temperature, but this is not...

Library 26- Rotary encoder on STM32F4 33

Library 26- Rotary encoder on STM32F4

A rotary encoder, also called a shaft encoder is an electro-mechanical device than converts the angular position or motion of a shaft to an analog or digital. There are 2 types of rotary encoders: Incremental – output indicates just rotation clockwise or counterclockwise Absolute – output indicates current position for encoder For that purpose I made a one simple library. This library works for incremental rotary encoders. It uses an interrupt to handle rotations. On the rotary encoders inside are...

STM32F4 External interrupts tutorial 122

STM32F4 External interrupts tutorial

Each STM32F4 device has 23 external interrupt or event sources. They are split into 2 sections. First interrupt section is for external pins (P0 to P15) on each port, and other section is for other events, like RTC interrupt, Ethernet interrupt, USB interrupt and so on. October 1, 2014: Added external interrupts library. GPIO as Interrupt Interrupt lines I will show now how to configure GPIO pin to be an interrupt and how to handle it in your code with...

Library 19- Use internal RTC on STM32F4 94

Library 19- Use internal RTC on STM32F4

It’s been some time when I post last library. Next one is internal RTC library. STM32F4xx devices have Real Time Clock (RTC) inside, with support of internal calibrated 32768 Hz oscillator or external (more accurate) 32768 Hz oscillator. RTC peripheral has also backup register support, which means that when you reset MCU, registers are not reset or if power is off and you have battery connected on Vbat pin, clock is still working. RTC can also wakeup MCU from all...

All STM32F4 libraries 123

All STM32F4 libraries

Because there is a lot of libraries I have done, I will make a table with all of my libraries at one place. When new library will be created, it will be posted here. These libraries work on both Discovery boards, if not, it will be specified. Actually, libraries should work on STM32F4xx series of microcontrollers if they have peripherals that are need for library. All STM32F4xx MCUs don’t have everything inside. 🙂 Libraries are tested on my 4 STM32F4...

STM32F4 NVIC or Nested Vector Interrupt Controller 35

STM32F4 NVIC or Nested Vector Interrupt Controller

Interrupts are important in microcontrollers. WIth them you are able to stop executing main program and jump to some predefined area if there is something important. I already used interrupts in my USART library. There is an interrupt called each time data arrive to MCU. Defferent peripheral can trigger interrupt, like data come to USART, ADC finished conversion, timer overflow, and more more. NVIC NVIC or Nested Vector Interrupt Controller is used to dinamically tell which interrupt is more important and...