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Unread 05-02-2004, 15:01
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Re: Control system response time and bandwidth?

Quote:
Originally Posted by KenWittlief
has anyone done any testing on the new control system to measure the following parameters?:

1. when you move a joystick, how long until the change in value is output to the mapped PWM (victor) when using the radio link?

2. if you change a PWM output in the code, how long until it is output to the PWM cable?

3. how long does it take to send out the full PWM command? ie, how long is the PWM signal period?

4. When an analog or digital input is changed at the input pins, how long until the code sees the new value in the corresponding variable?

I didnt see this info in the specs for the OI and RC - if you know where to find it please point me in the right direction - if you have NOT actually measured it with a scope, please dont guess - if nobody knows for certain I will drag my digital scope to our site tonight and measure them.
Well according to the IFI page:

Digital Input Frequency (typical) 50 KHz
Analog Input Access Time 10 μSec

The analog time seems reasonable according to the actual specs for the microcontroller, though I do wonder about the digital what exactly they are measuring with the digital inputs, since you should see the change almost immediately, (since the digital IO pins are connected directly to the I/O ports on the micro)