St10F269 ADC autoscan and digital input

[thomaskobler9]

Posted on June 29, 2006 at 10:47

St10F269 ADC autoscan and digital input

[thomaskobler9]

Posted on June 29, 2006 at 06:33

Why is the digital reading of 'autoscanned' analog inputs completely unreliable and wrong, even when the discriminator/hysteresis (P5DIDIS) is switched on (temporarily). It only works, when the ADC ist stopped and autoscan is reastarted without the channels to be read digital.

Is this documented somewhere? Is it a bug? A feature?

Thank you.

[thomaskobler9]

Posted on June 29, 2006 at 10:47

> Have you tested the case of signle ADC conversion of a channel

No, neither starting nor reading result, cause this wouldn't have been possible in our application: the digital and analog reading are asyncronous.

The pin is used with an NTC and as a general error indication at the same time, when pulled low. Because analog data gets averaged in the ISR, the digital reading is usefull, to quickly check if the pin is pulled low.

We don't use PEC, but an ISR to readout the analog result and process it. No overrun. The digital bit get's polled at times.

Thank you.