ws2812 change from opendrain to push_pull output #44
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with open drain the driver doesn't work very well on hardware with inline resistance between the stm32 and output pins. Changing to push_pull output means it works reliably with a 1k resistor inline for pin protection.
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The reason for opendrain is that some (most) LEDs require more than 3.3V on the data-pin. On 5V-tolerant pins (most are) you can use a pull-up to 5V and opendrain to make it work. If the pins are in push-pull the simple pull-up trick won't work. Maybe there should be an option to switch between open-drain and push-pull? |
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The leds I am using say 0.7xVcc so 3.5v but seems to work fine with 3.3v. |
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with open drain the driver doesn't work on hardware with inline resistance between the stm32 and output pins. Changing to push_pull output means it works reliably with a 1k resistor inline for pin protection.