Re: view the wave signal of function generator to the pc thr
This is a good question.
It is best not to modify/attentuate the signal to sample as original as possible.
Because the process might destroy your signal.
Like what you mention, in practise it may result in extra circuitry.
Some ADC allow configuration to digitise a wider range of voltage level.
Even in PIC microcontroller, which uses 5V,
the ADC itself, if I can remember correctly, can
also sample signal at a wider voltage by setting the reference voltage.
Sampling the attenuated signal simply means the loss in resolution.
In order to achieve better resolution after attenuation,
a higher bit ADC helps but to certain extend.
It is much more difficult to sample low amplitude signal,
for it behavior much like noise.
You have to decide what you want.
If the modification to your signal do not affect your application,
by all means attenuate your signal....
as much as possible try to preserve the original signal form.
Sincerely,
Siong Boon