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How are the GPIO pins named in STM32?
Raw GPIO pin access On ARM, each pin is a bit in a hardware port, mapped to a specific memory location. Naming is straightforward: each port is a letter (“A” to “K”), with up to 16 pins (0 to 15). The STM32 naming convention for pin 13 of port B is
Can a GPIO pin be set to output mode?
When a GPIO pin is set to output mode, you’ll have the option to configure the pin speed mode by programming the respective bits in the configuration registers. Down below is a table for the different modes available in the datasheet for the STM32F103C8 microcontroller.
What is the toggle rate on the STM32?
The LED will blink FAR too quickly to see, but with the F407 clock running at its 16 MHz default and a frequency meter, the pin toggle rate can be measured: it’s 0.79 MHz. It looks like each loop iteration needs 10 clock cycles (two toggles make a full on/off cycle). Some overhead is due to the loop itself.
What are the different modes of the STM32 microcontroller?
Down below is a table for the different modes available in the datasheet for the STM32F103C8 microcontroller. However, other microcontrollers will have different options for the pin output speed. For example, the other microcontroller we’ll be using in this course STM32L432KC.
How is the GPIO pin connected to the led?
On the board I’m using, the LED is connected between the I/O pin and +3.3V (via a current-limiting resistor). This makes that I/O signal “active low”, i.e. its active state (LED on) is when the GPIO pin is low (“0”). Hence the inverted logic. So much for the really low-level(and tedious!) way of controlling a GPIO pin. GPIO pins in C++
How are pins mapped to variables in Jeeh?
In the JeeH library, pins can be mapped to variables using a special notation in C++, so with our LED on pin PB13, a variable named “led” can be declared as follows: PinB<13> led; This uses C++ templates, hence the <>notation in there. Setting the pin to behave as an output is now one call: led.mode(Pinmode::out);