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WP34s 20b power-on delay - Printable Version

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WP34s 20b power-on delay - MarkHaysHarris777 - 02-13-2015 07:08 AM

Greetings, I am noticing a 1-2 second power-on delay, with my 20b unit (34S 3.3T 3742) after sitting some time. If the unit has only been 'off' for a short time the power-on is instantaneous. If it has been 'off' for half an hour or more then 1-2 sec power up delay. Has anyone else noticed this. This occurs regardless of whether the proc is running 'fast' | 'slow'; also don't notice anything else amiss. Of course it takes 'days' to put this thing through full testing; but all else seems ok.

TIA


marcus


RE: WP34s 20b power-on delay - Paul Dale - 02-13-2015 07:17 AM

I noticed the same thing on my 30b WP 34S.
Marcus is the person for this one.


- Pauli


RE: WP34s 20b power-on delay - -whs- - 02-13-2015 09:36 AM

Hello,

I observed this with my 30b WP34s too. After this occurs the settings of
DATE and TIME are reset. I have to set these values new.

Walter


RE: WP34s 20b power-on delay - MarkHaysHarris777 - 02-13-2015 10:08 AM

I am wondering if it has to do with unit power and whether the proc shifts into 'slow' speed on power-up?

(see my other post Power Proc-Speed Performance)

marcus


RE: WP34s 20b power-on delay - Marcus von Cube - 02-13-2015 06:37 PM

(02-13-2015 10:08 AM)MarkHaysHarris777 Wrote:  I am wondering if it has to do with unit power and whether the proc shifts into 'slow' speed on power-up?

The reason must be a total loss of power. The delay is caused by the boot up sequence when it sets up the quartz oscillator and waits for it to stabilize. In normal operation this step is not needed because the oscillator keeps running even in deep sleep mode.


RE: WP34s 20b power-on delay - MarkHaysHarris777 - 02-13-2015 07:36 PM

(02-13-2015 06:37 PM)Marcus von Cube Wrote:  
(02-13-2015 10:08 AM)MarkHaysHarris777 Wrote:  I am wondering if it has to do with unit power and whether the proc shifts into 'slow' speed on power-up?

The reason must be a total loss of power. The delay is caused by the boot up sequence when it sets up the quartz oscillator and waits for it to stabilize. In normal operation this step is not needed because the oscillator keeps running even in deep sleep mode.

Thanks, again Marcus. After I replaced the coin cells and reset date & time the power-on delay has vaporized. whoohoo

Its nice to understand what's going on, and its nice to have it corrected too. The lesson in the last couple of power posts is that these units draw so little current (operate at such low mW normally) that the voltage drop read by the 'BATT' function really can't be taken as a valid readout of the unit's ability to function under load with that set of coin cells. In other words, the real voltage must be considered under load only.

Kind regards,
marcus
Smile