Duty Cycle using PCA

[luigi2]

Posted on March 31, 2005 at 05:23

Duty Cycle using PCA

[luigi2]

Posted on May 17, 2011 at 12:06

Hello,

I would calculate a duty-cycle usig the programmable counter array but I have confused ideas can to indicate some example to me

TKS

[gianluca2]

Posted on May 17, 2011 at 12:06

I have the same problem,

I'm new to the uPSD, I have a DK3300 board and I want to interface a 2-axis accelerometer with PWM output, so my need is to decode the PWM ratio coming from an external signal.

My problem is the configuration for the interrupt vectors;I can configure the registers following the user manual, but where do I define the interrupt vectors for the PCA?

thank you very much!

:-[

[rk1]

Posted on May 17, 2011 at 12:06

hi,

assumed that you consider ''all-high''=0% and ''all-low''=100% duty-cycle (''active-low''):

duty-cycle = CAPCOM_value / (max_counter_value+1)

if you consider ''all-low''=0% and ''all-high''=100% duty-cycle:

duty-cycle = (max_counter_value+1 - CAPCOM_value) / (max_counter_value+1)

where:

max_counter_value+1 = 2^8 for 8-bit-PWM, 2^16 for 16-bit-PWM

(see datasheet: the output is high when the PCA-counter equals or exceeds the CAPCOM-value)

[luigi2]

Posted on May 17, 2011 at 12:06

The interrupt vector for uPsd33xx identifies all interrupt and it is declarer in ups3300.h however the pca interrupt is the number 11