[PD] Firmata polling routines

marius schebella marius.schebella at gmail.com
Sun Aug 17 19:37:04 CEST 2008

Adityo Pratomo wrote:
 > so there's an interrupt routine there? And is the routine controlled
 > in the arduino code, not in the pure data?

Firmata computation runs in a loop. The first step is to check for 
changing values at the digital inlets and immediately send them to Pd 
without delay. The second step is executed every 20 milliseconds. During 
that call, all data that was received from Pd is handled and the analog 
inputs are read and sent to Pd.
I am not exactly sure how the second step is triggered, if it has a 
timer, interrupt or just runs as fast as possible. but it is definitely 
not triggered by Pd.

 > On 8/17/08, marius schebella <marius.schebella at gmail.com> wrote:
 >> Adityo Pratomo wrote:
 >>> Hi there everyone. Can anybody explain to me how the polling routine
 >>> on firmata works when handling multiple sensors input? I'm trying to
 >>> found out myself, but i still couldn't get it. Or is it actually not a
 >>> polling at all?
 >> I think arduino sends automatically, so no polling. whatever inputs are
 >> enabled/turned on, will automatically get sent by the firmata protocoll.
 >> I guess the rate is 50 times per seconds/every 20ms.
 >> and afaik the digital ins run in a separate loop that fire a message
 >> whenever there is a change.
 >> marius.

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