GPIOB Pin 5 Configuration: General Purpose Output with 50 MHz Speed

To set pin 5 of GPIOB as a general purpose output with a maximum output speed of 50 MHz, we can follow a step-by-step procedure using bitwise operations. Let's go through the process:

Step 1: Set the corresponding bit in the GPIOB mode register (GPIOB_MODER) to enable general purpose output for pin 5.

• Read the current value of GPIOB_MODER.
• Clear the bits corresponding to pin 5 by applying a bitwise AND operation with a mask where only the bits corresponding to pin 5 are set to 0.
• Set the bits corresponding to pin 5 as output by applying a bitwise OR operation with a mask where only the bits corresponding to pin 5 are set to 1.
• Write the modified value back to GPIOB_MODER.

Step 2: Set the corresponding bits in the GPIOB output type register (GPIOB_OTYPER) to configure the output as push-pull (default state).

• Read the current value of GPIOB_OTYPER.
• Clear the bits corresponding to pin 5 by applying a bitwise AND operation with a mask where only the bits corresponding to pin 5 are set to 0.
• Write the modified value back to GPIOB_OTYPER.

Step 3: Set the corresponding bits in the GPIOB output speed register (GPIOB_OSPEEDR) to configure the maximum output speed (50 MHz) for pin 5.

• Read the current value of GPIOB_OSPEEDR.
• Clear the bits corresponding to pin 5 by applying a bitwise AND operation with a mask where only the bits corresponding to pin 5 are set to 0.
• Set the bits corresponding to pin 5 as high speed (11) by applying a bitwise OR operation with a mask where only the bits corresponding to pin 5 are set to 11.
• Write the modified value back to GPIOB_OSPEEDR.

Now, let's write the code to accomplish these steps:

// Step 1: Set GPIOB pin 5 as general purpose output
uint32_t* GPIOB_MODER = (uint32_t*) 0x40020400; // Address of GPIOB_MODER register
uint32_t gpioModerValue = *GPIOB_MODER; // Read the current value of GPIOB_MODER

// Clear the bits corresponding to pin 5
gpioModerValue &= ~(3 << (5 * 2));

// Set the bits corresponding to pin 5 as output
gpioModerValue |= (1 << (5 * 2));

*GPIOB_MODER = gpioModerValue; // Write the modified value back to GPIOB_MODER

// Step 2: Configure GPIOB pin 5 as push-pull output
uint32_t* GPIOB_OTYPER = (uint32_t*) 0x40020404; // Address of GPIOB_OTYPER register
uint32_t gpioOtyperValue = *GPIOB_OTYPER; // Read the current value of GPIOB_OTYPER

// Clear the bits corresponding to pin 5
gpioOtyperValue &= ~(1 << 5);

*GPIOB_OTYPER = gpioOtyperValue; // Write the modified value back to GPIOB_OTYPER

// Step 3: Configure GPIOB pin 5 with maximum output speed (50 MHz)
uint32_t* GPIOB_OSPEEDR = (uint32_t*) 0x40020408; // Address of GPIOB_OSPEEDR register
uint32_t gpioOspeedrValue = *GPIOB_OSPEEDR; // Read the current value of GPIOB_OSPEEDR

// Clear the bits corresponding to pin 5
gpioOspeedrValue &= ~(3 << (5 * 2));

// Set the bits corresponding to pin 5 as high speed (11)
gpioOspeedrValue |= (3 << (5 * 2));

*GPIOB_OSPEEDR = gpioOspeedrValue; // Write the modified value back to GPIOB_OSPEEDR

This code sets pin 5 of GPIOB as a general purpose output with a maximum output speed of 50 MHz using bitwise operations as described in the step-by-step procedure. It first accesses the relevant registers' addresses, performs the necessary bitwise operations, and writes the modified values back to the registers.