Dual use AD pins
Posted: Wed Jan 30, 2013 4:11 pm
My answer would be the same as when I was TA'ing CS courses, "I don't know, why
don't try it and tell me what happens?"
My guess would be if the cap is big enough and you write directly to the FIOxDIR
pin to disable the digital drive and then the PINSEL register you might have it
work.
--- In ARMexpress@yahoogroups.com, "pompey2" wrote:
>
> " On reset or power up the AD pins are configured as AD inputs. To change
those to digital IOs, the user must individually specify a control direction
using INPUT x, OUTPUT x, DIR(x), or IO(x) commands. After that they will
remain digital IOs until the next reset or power up."
>
> Is there a non-disruptive way, writing '11' to the appropriate bits of Pinselx
for example, to switch back to AD Inputs? I'd like to discharge a capacitor to
Gnd, then measure the time to reach specific trip voltages as it recharges
through a thermistor, and would like to use 1 pin.
>
> Chris
don't try it and tell me what happens?"
My guess would be if the cap is big enough and you write directly to the FIOxDIR
pin to disable the digital drive and then the PINSEL register you might have it
work.
--- In ARMexpress@yahoogroups.com, "pompey2" wrote:
>
> " On reset or power up the AD pins are configured as AD inputs. To change
those to digital IOs, the user must individually specify a control direction
using INPUT x, OUTPUT x, DIR(x), or IO(x) commands. After that they will
remain digital IOs until the next reset or power up."
>
> Is there a non-disruptive way, writing '11' to the appropriate bits of Pinselx
for example, to switch back to AD Inputs? I'd like to discharge a capacitor to
Gnd, then measure the time to reach specific trip voltages as it recharges
through a thermistor, and would like to use 1 pin.
>
> Chris