Hi,
Let's say you connected a led to GPIO F7.
If you are not using CW with PE, and want to handle it manually, several registers involved:
Initialization:
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GPIOF_PUR &= 0xFF7F - clr power up resistor bit to disable function.
GPIOF_DDR |= 0x0080 - set DDR bit for OUTPUT mode
GPIOF_PER &= 0xFF7F - set as simple GPIO function
GPIOF_PPMODE |=0x0080 - set port to push-pull mode
pin activity:
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Now you can set pin to 1 by GPIOF_DR |= 0x0080 or 0 by GPIOF_DR &= 0xFF7F