I can’t find accurate info anywhere about the digital out operating frequency. We know that K8055 board has 20 ms response time, so its 1/0.02 = 50 Hz max speed? So by using digital out and let’s say mosfet driver with power mosfet we can get a PWM with a 50Hz frequency? So 30Hz controling little servos should be no problem?
Also another question is how fast ADC converter works? And what type it is? SAR, Pipeline, integrating? That info is missing in the PIC controller datasheet, or i’ve just missed. I want to know the discretization time. Quantation 8 bits, so it has 256 levels and should be quite fast.
[quote]I can’t find accurate info anywhere about the digital out operating frequency.[/quote]The output response time is according to the USB specifications 10ms max. Typically it seems to be about 8ms. So the max digital output frequency is about 62Hz.
Here an oscilloscope screenshot image:
This is the code:
for (int i= 0; i< 100; i++)
{
SetDigitalChannel(1);
ClearDigitalChannel(1);
}
To get some pulse width modulation you can adjust the low period or the high period in steps of 8ms.
In this case the low period is increased to 16ms:
[quote]Also another question is how fast ADC converter works? And what type it is? SAR, Pipeline, integrating?[/quote] Seems to be SAR.
A snippet from datasheet:
[color=#008000][size=85]The output of the
sample and hold is the input into the converter, which
generates the result via successive approximation. [/size][/color]
[quote]I’ve got another question though. What is the maximum signal frequency on inputs? is it 2 kHz? i’ve saw somewhere that counter can count up to 2 kHz [/quote]Yes, it is 2kHz.
The duty cycle have to be 50% in this case.
On lower frequency there is no need to have 50% duty cycle but the pulse and pause periods have to be > 0.25ms.
