Hello,
I am using NXP Xpresso V2 board for LPC11U37H. I am trying to blink on board LED's by reading SW1 and SW2. To sense SW1 and SW2, I am using API library functions, Board_Buttons_Init(), ButtonsGetStatus().
With this I am able to sense SW2 properly but SW1 is always pressed detected. My question is, because SW1 is connected to WAKEUP pin and supplying external voltage, do I need to initialize this GPIO in different manner as of GPIO of SW2 ? Is this triggering SW1 to detect always pressed?
Original Attachment has been moved to: board.c.zip
Hi,
enable internal pull-up for this pin or connect it via resistor 1-100 kOhm to 3.3 V.
Hi Pavel,
I tried by activating internal pull up for that pin but still detecting as switch is pressed.
Regards,
Ojas
I'm sorry, I mistook SW1 with SW2. SW1 have pull-up R73 and not need internal.
:-)
Hi Ojas,
Check your RV2 setting. If it is shorting to ground your signal will not ever be high (deasserted).
If it is set so PIO0_16-ADC_5-WAKEUP is high, I think it should work (I don’t have a board but looked at schematic).
Regards,
David
Hi David,
Good observation, I checked for RV2 but it is not shorted to ground. Looks like have some other issue.
Regards,
Ojas
This is probably the right direction. You must set the trimmer to majority from the 3.3 V.
Attention: At 100%, or very close to 100% SW1 cannot able to decrease voltage bellow threshold, because R66 prevents it.
(I do not know if I wrote it correctly in English)