LPC11C24 is it possible to change the reset state of pins?

[davidesalvetti]

Hi,

on my LPC11C24 I need to upgrade the firmware but when the micro restarts, all the GPIOs go high cause of the internal pull-up resistors . I'm wondering if it's possible to change the reset state of those pins before adding some external pull-down resistor to solve the problem.

Thank you for your help in this matter.

Davide Salvetti

[Carlos_Mendoza · Accepted solution]

Hi Davide,

From startup of the supply (0v) till about 1.8v the MCU is in an undefined state, above 1.8v the I/O pins will be in the default configuration which is input with pull-up enabled. The default state can’t be controlled trough software, but you could add a stronger external pull down to override that state.

Hope it helps!

Best Regards,
Carlos Mendoza
Technical Support Engineer