You never will, because a beast like that does not make sense, as has been explained to you earlier.

Sorry dhenry ... where exacly was has been explained ?

Look into the device datasheet for that. Can be less than 1ua, depending on the rtc and mode you are  running it in.

Whoau ... great thinks
So now I only most fount an RTC that give me the millis
can anybody target me to some of this RTC please ?
Thanks again
Denis

Is there nowhere near an electric meter that you can plug a USB charger in?

The problem is not the power, i just want to make it run from 2 X 1.5 Batts cause i'm sure it can run some mounts if i make it right ;-)

Why? Don't you just want to count the number of pulses over 5 minutes? If you want to know the number of watts, who cares when the pulse occurred, to the nearest millisecond?

Nick, i will need to send 2 types of data on the net ...
1. the actual power that the PV system generate, for this i'll need the time between last 2 pulses every 5 minutes
2. the total generated power, and here i'll count all pulses of that day.

If that's what you truly want to do, look into msp430: their crystal oscillator is "instant on". on that.

Dhenry ... I allready have difficult to understand this world cause I'm newbe, thansk a lot but i don't want to go versus new mcu's

I want to ask something also.
In the link of Nick page http://www.gammon.com.au/forum/?id=11497 i so the difference from
SLEEP_MODE_PWR_SAVE: 1.62 mA - this I can use if I'll use the external Timer2 using the 32KHz cristal
SLEEP_MODE_PWR_DOWN : 0.36 mA - for this mode I'll use the external RTC chip.
...so the diff is 1.26 mA
My question is... how much ampere an external RTC can use ? ...less than 1.26 I hope right ?

Thanks again all
Denis

Nik,
thanks again for your answer.
Like you can understand, I'm trying to keep the hardware as simple as possible.

I will not need a like a calendar time ... but just to have the millis between last 2 pulses.
So i search some RTC that have a millis also... but i don't find for now.
For example i found DS3232 from Maxim and on the key fastures i read:
Real-Time Clock Counts Seconds, Minutes, Hours, Day, Date, Month, and Year with Leap Year Compensation Valid Up to 2099

It is there something that give me the mills ? i don't need other ... as little is possible :-)

Can i use the RTC with the current from the principal batteries ? so with out the battery backup.
After the reset I'll set to 0000 the time and then will count only the mills between last 2 pulses.
Then every 5 minutes wakeup, send the watt/hour via RF and i'll turn the RTC to 0000, then back to shutdown.
I think in this mode will consume less power.

GoForSmoke@ ... the current meters in Italy have only the LED that emit a pulse every watt, there is not the time :-(

Thanks again all
Denis

Dear Nick,
thanks a lot for your big help
I was out of home all weekend, and i can't replay.

My simply opinion is that 2 uA it's very good.
So for the timer... you think that is better if i put there an external  RTC chip ?
...or is better using external 32Mhz crystal for timer2, and internal oscillator at 8MHz ? in this case i must flash it different right ?

I'm looking for some LLS05-A linear light sensor... but i already have some photo-resistance maybe i'll test using that.
Again thanks to all   
Denis

Thanks a lot all of you guys ... it's wonderfool to see a lot of help.

I just ordered yesterday some 32,768 MHz crystals in order
to begin to test it.

So after i read (but not understand all) the wonderfool article post by Nick (http://www.gammon.com.au/power)
i understand this steps:

- i must run it using the Timer2 trained by an 32MHz external quartz in order to have an accurate time after wake up
- i must program the atmel in order to use 8MHz (i anyway need at last 4Mhz in order to use the RFM12B for rf transmitter)
- for the LED pulse i will use the LOW interrupt wake-up on pin 5 of atmel
  (i hope will fill the LOW status, cause now in my program i use the RISING status)

Is everything right until now ?
The Timer2 is work in "Power Down" mode ? ..or it's work only in "Power Save" mode ?

I just must understand about how to program the atmel in this case.
If I understand I can not use the normal flash using the bootloader
cause of use of internal 8MHz RC clock... it is there a bootloader that can use 8MHz internal clock ?

Thanks a lot again
Denis

Dear Nick,
thanks again for the help

I don't know what type of interrupt I use ... i just copy paste the command from some source around
I know that I activate it using:

Code:

attachInterrupt(1, onPulse, RISING);

It is the LOW interrupt please ?
Thanks a lot
Denis

Hi there and thanks all for the answer.

Now I don't remember where I read but I remember that tha cpu can sleep
but have also the external interrupt active.
Is this true ?

The LED pulse is read from a photo transistor
like here: http://forum.jeelabs.net/files/monitor_design_v01.png

It must wake up every 5 min in order to send the data via RF
but also must wake up every pulse that arrive via interrupt in order to count it.

Can I put it in sleep but external interrupt active please ?

Thanks again
Denis

Hi there all,
I'm a newbe and i finish to read some articles
about power saving of arduino.
i just want to ask you a little question.

I have a pulse counter that i want to make it to save more power possible.
This pulse sensor must read a LED pulse of my current power meter
and then send it via RF every 5 minutes to another arduino base.
Must work using 2 X 1.5 V Batts.

If i understand the most of CPU can be shut down in order to consume less power.
The problem is that i need an accurate timer in order to know
the time between the last 2 pulses every about 5 minutes.

So if I power down the arduino, i lost the mills().
But if i use an external timer2 using an external 32 KHz crystal
i can wakeup and have also the accurate timer2 mills... is this true ?
Is this correct that i understand please ?

Thanks a lot
Denis

Bellissimo progetto Bruno,
mi permetto di rispondere anche se fin ora ho solo letto.

Io sto facendo una cosa simile, ma ho preferito andare a leggere gli impulsi del led del contattore produzione FV
Ho un impianto (casa privata) da 7 kw nella zona Mi Sud.

Uso un arduino fatto sulla board collgato ad un modulo RF ed alimentato con 2 batterie.
Legge gli impulsi ed ogni 5 min mi manda l'attuale potenza ed il watts generati nei 5 minuti.

Poi via radio viene acchiappato da un nanoderf (http://solderpad.com/monsonite/nanode-rf/)
e lo manda in rete (attualmente uso pachube) per darmi la grafica produzione.

Ti posso suggerire se ti va il display piccolo che tua moglie (come la mia:-) puo vedere sempre con la produzione.
Anche il display ha il modulo RF (http://openenergymonitor.org/emon/emonglcd)

Quello che vorrei, quando sarà finito, e poter vedere on line, e sul display in casa, tutta la produzione e magari alcuni apparecchi che consumano tanto
(costruirmi delle spine con arduino + RF dentro) che possono mandare il segnale sia al display che al nanoderf per la rete.

Sono al inizio, e sono nuovo nell'elettronica, ma comincio a capire tante bele cose :-)

Ah... complimenti per il forum, sto imparando tante cosine da voi :-)

Denis

Aia... che vergogna,
ho sbagliato il nome SCUSATE !!!

Volevo dire ovviamente arduino. Che figuraccia che ho fato già al primo post
Scusate ancora :-)

Denis

Ciao a tutti
e come prima cosa complimenti per il forum e per l'aiuto che ho trovato solo leggendo

Sono qui a scrivere il mio primo post per chiedere aiuto per un
acquisto. Non ho mai avuto a che fare con il narduino, ma la cosa mi piace un casino.

Vorrei mettere appunto un progetto che mi permetta di leggere
la potenza che passa sui cavi in casa mia.
Ho un impianto fotovoltaico che produce quasi sempre piu di quanto
consuma la casa.

Devo leggere quindi l'uscita del inverter fotovoltaico(produzione)
e devo leggere l'entrata in casa della corrente(consumo)
questo per sapere quanto fa la produzione - consumo = potenza disponibile da consumare

Il tutto deve essere mandato via ZigBee al narduino, che poi vorrei collegarlo nella rete lan.

Vi chiedo quindi un aiuto per la lista dei giocatoli da acquistare.

Arduino: non so ancora se comprare arduino uno oppure il mega2560 che e piu potente
...rimango per il mega che forse va piu di moda.

XBee: qui comincio ad avere dei dubbi... perché so che mi serve un xbee per il narduino
per poter ricevere il segnale dalle sonde, ma non so quale acquistare dei tanti.
Poi per leggere la potenza dei cavi e trasmetterla come posso fare ?

Ethernet:  anche qui mi dovete aiutare perche mi serve sapere per prima cosa
se sul narduino si puo mettere sia la xbee che la sch.ethernet nello stesso tempo.

Scusate ma e solo oggi che ho scoperto il mondo narduino e non ho ancora capito se e cosi modulare.

Be... se siete arrivati fin qui, vi ringrazio già solo per aver letto il post :-)

Grazie a tutti
Denis