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5 years, 1 month ago.
What is the fastest way to turn-on a GPIO from power-on?
I'm developing a project in mbed for the nRF51822 chip. Currently using the nRF51-DK board for prototyping.
I need the chip to turn on GPIO pin on (setting it high) as fast as possible after start-up. Currently it's taking 350ms looking on my oscilloscope... This seems pretty huge...
My code is not doing anything much beyond starting-up and setting this pin. It sets-up Serial objects & one or two other pins a bit later, but I try to set the pin's initial value as quickly as possible using: - DigitalOut(thePin,1);
What some ways (if any) I could improve this start-up time?
I know that, often, the big delays in start-up are to do with starting oscillators and perhaps the nRF51's DC/DC converter if it's using that.
Are there any standard mbed ways to quickly set a GPIO as fast as possible before any other code is executed?
Any other suggestions to reduce start-up time?