Powering the calculator from the USB port

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Michael
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Re: Powering the calculator from the USB port

Post by Michael »

Boub65 wrote: ↑
Thu Dec 21, 2017 12:17 pm
 I learned that Original Samsung fast USB Chargers are 5V/9V...
So it's a no no no!
The default voltages of all USB chargers is 5V. Any higher voltage has to negotiated.
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HPMike
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Location: DFW, Texas

Re: Powering the calculator from the USB port

Post by HPMike »

Does the DM42 have an annunciator to indicate connection to a USB power supply ?
DM15L, S/N 00548. DM42, SN: 00159. DM41X, SN: 00973. DM32, SN 00054.
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grsbanks
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Re: Powering the calculator from the USB port

Post by grsbanks »

Yes.

The battery "icon" in the top-right becomes a USB logo.
There are only 10 kinds of people in the world: those who understand binary and those who do not.
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HPMike
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Re: Powering the calculator from the USB port

Post by HPMike »

grsbanks wrote: ↑
Thu Dec 21, 2017 4:56 pm
 The battery "icon" in the top-right becomes a USB logo.
I just confirmed this using the USB cable and charger for my HP Prime. I can can also confirm that my DM42 did not explode. :D
DM15L, S/N 00548. DM42, SN: 00159. DM41X, SN: 00973. DM32, SN 00054.
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rprosperi
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Re: Powering the calculator from the USB port

Post by rprosperi »

HPMike wrote: ↑
Thu Dec 21, 2017 5:29 pm
 I just confirmed this using the USB cable and charger for my HP Prime. I can can also confirm that my DM42 did not explode. :D
Oh, well sure it's fine with the Prime charger; your original question was about using your iPhone charger, well known to dislike non-Apple products ;)
--bob p

DM42: β00071 & 00282, DM41X: β00071 & 00656, DM10L: 071/100
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Boub65
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Re: Powering the calculator from the USB port

Post by Boub65 »

Michael wrote: ↑
Thu Dec 21, 2017 4:10 pm
 The default voltages of all USB chargers is 5V. Any higher voltage has to negotiated.
Please @Michael, have a look at the characteristics of an USB SAMSUNG Traveler Adapter...
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Sincèrement, Sincerely, 73,
Boubker

DM15L, DM41L, DM42 #00855 (domes upgraded), DM41X #00707
HP48SX (with dark screen), HP42s, HP32SII (1990 with fraction bug), HP41C/CV
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Michael
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Re: Powering the calculator from the USB port

Post by Michael »

Boub65 wrote: ↑
Thu Dec 21, 2017 10:55 pm
Michael wrote: ↑
Thu Dec 21, 2017 4:10 pm
 The default voltages of all USB chargers is 5V. Any higher voltage has to negotiated.
Please @Michael, have a look at the characteristics of an USB SAMSUNG Traveler Adapter...
Please give it a try and I'll send you a replacement if it explodes.
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Boub65
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Re: Powering the calculator from the USB port

Post by Boub65 »

Michael wrote: ↑
Thu Dec 21, 2017 10:58 pm
 Please give it a try and I'll send you a replacement if it explodes.
No no no... I will not try @Michael on my (future) DM42...😁
Sincèrement, Sincerely, 73,
Boubker

DM15L, DM41L, DM42 #00855 (domes upgraded), DM41X #00707
HP48SX (with dark screen), HP42s, HP32SII (1990 with fraction bug), HP41C/CV
TI-89 titanium, CASIO fx-cg50 and Numworks (to play with micropython)
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rprosperi
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Location: New York

Re: Powering the calculator from the USB port

Post by rprosperi »

Michael wrote: ↑
Thu Dec 21, 2017 10:58 pm
 Please give it a try and I'll send you a replacement if it explodes.
You kill me... so dry... :lol:
--bob p

DM42: β00071 & 00282, DM41X: β00071 & 00656, DM10L: 071/100
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Guenter
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Re: Powering the calculator from the USB port

Post by Guenter »

rprosperi wrote: ↑
Thu Dec 21, 2017 11:16 pm
Michael wrote: ↑
Thu Dec 21, 2017 10:58 pm
 Please give it a try and I'll send you a replacement if it explodes.
You kill me... so dry... :lol:
Michael did obvioudly read the various specs about quick charge, where indeed higher voltages than 5V are offered. BUT the important thing is both partners, charger and device, must be able to negotiate on the voltage. If that's not the case they fall back to 5V which is USB standard. So, yes the mentioned Samsung charger is able to deliver 9V but will not do so if the client is not properly (with the right protocol) asking for it. I guess Michael knows for sure that the DM42 doesn't do that.

Günter
Günter
DM42 SN:00004 and SN:00184 -- DM41X SN:00013 and SN:00955
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