Power OFF mode

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hsilop
Posts: 21
Joined: Thu Mar 14, 2019 12:35 am
Location: Canberra, Australia

Power OFF mode

Post by hsilop » Thu Mar 14, 2019 7:19 am

In the System>Enter System Menu there is an option on line 7 to change the Power OFF mode. If cycles between 0 and 3. But what do these values mean? Can't find anything about it in the documentation.

Awesome calculator BTW - I haven't been able to put it down in 2 days!
DM42 SN: 03223

HP-25, HP-33C, HP-41CV, HP-46, HP-11C, HP-12C, HP-15C, HP-16C

StreakyCobra
Posts: 8
Joined: Thu Jun 14, 2018 8:09 am

Re: Power OFF mode

Post by StreakyCobra » Thu Mar 14, 2019 9:05 am

It is maybe not explained in the help file on your calculator, but it is explained in the online official documentation:
This item is purely for power OFF testing purposes to avoid time consuming switching between firmwares. It is in no way mentioned to be changed by users.

Mode 0 means no deep sleep for QSPI giving approx. 12uA sleep current.

Mode 1 corresponds to pre 3.9 DMCP behavior.

Mode 2 corresponds to DMCP 3.9 and newer versions.

Mode 3 is latest update to mode 2 which should fix possible deficiencies of mode 2 by adding further pull-ups.

Defaults:

hwid=0 : Mode 1
hwid=1 : Mode 3

Note that the "Power OFF mode" value is preserved during calculator RESET, but is lost when battery is removed.
It as also been discussed there:
I can only report what David wrote me last october, while testing my beta unit that showed high current drain with firmwares > 3.9.
I don't know if all of this is still valid, I hope DM will soon release more info on this setting.
There is new item in System submenu "Power OFF mode". So, no need to
switch between firmwares to test different power off mode behaviors.
For you should work mode0 (which means no deep sleep for QSPI giving
~12uA sleep current) and mode1 (which corresponds to pre 3.9 fws -
which should give ~4-5uA on your machine. Modes 2 corresponds to 3.9
and further and mode 3 is very last update to mode 2 which should fix
theoretical deficiencies of mode2 and should be default in further
releases.

Note that the "Power OFF mode" values is preserved during calculator
RESETs, but is lost when battery is removed.

hsilop
Posts: 21
Joined: Thu Mar 14, 2019 12:35 am
Location: Canberra, Australia

Re: Power OFF mode

Post by hsilop » Thu Mar 14, 2019 10:35 am

Okay, thanks. I think I'll leave that well alone.

Seems I was somehow looking at an older user manual - D'oh!
https://www.swissmicros.com/dm42/doc/dm ... manual.pdf
DM42 SN: 03223

HP-25, HP-33C, HP-41CV, HP-46, HP-11C, HP-12C, HP-15C, HP-16C

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rkf
Posts: 10
Joined: Mon Mar 05, 2018 9:14 am
Location: Stade, Germany

Re: Power OFF mode

Post by rkf » Thu Mar 14, 2019 11:54 am

StreakyCobra wrote:
Thu Mar 14, 2019 9:05 am
...
hwid=0 : Mode 1
hwid=1 : Mode 3
...
Unfortunately, neither in the manual, nor (according to google) anywhere else is explained what hwid=[0|1] means. :(

Educated guess: hwid = Hardware ID. But how to detect, which hwid has a DM42, and what's the difference between 0 and 1?
DM42 S/N 00761

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akaTB
Posts: 241
Joined: Tue May 02, 2017 11:56 am

Re: Power OFF mode

Post by akaTB » Thu Mar 14, 2019 12:49 pm

rkf wrote:
Thu Mar 14, 2019 11:54 am
StreakyCobra wrote:
Thu Mar 14, 2019 9:05 am
...
hwid=0 : Mode 1
hwid=1 : Mode 3
...
Unfortunately, neither in the manual, nor (according to google) anywhere else is explained what hwid=[0|1] means. :(

Educated guess: hwid = Hardware ID. But how to detect, which hwid has a DM42, and what's the difference between 0 and 1?
Mine, being a beta unit, I'm pretty sure it is an hwid=0... ;)

However current firmware detects where it is running on, and sets the correct value. I think you don't need to play with it, but you can, of course: what you should expect is a change in current drain from your battery. You should be able to tell the difference even looking at the on-screen voltage indicator.
Greetings,
    Massimo

-+×÷ ↔ left is right and right is wrong

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