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> Hardware layout: battery, main screen hardware
NormMonkey
post Nov 28 2019, 12:11 PM
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Hi all,

I thought the battery on the Cosmo was under the keyboard. I even remember reading how the hardware team added a super-capacitor to ease power transfer to the other side. However, when I'm charging, it feels like the top (right under the cover display) is warm, while the other side is cold. Where is the battery located?

I'm also curious what's the little oval on the right side of the main screen? I thought it was a light sensor. However, when I turn on Adaptive Brightness, the display adapts to light levels on the Cover Display side of the device rather than the main screen side.
I can confirm using a Sensors app that the light sensor reacts to something located betwixt the cover camera and the cover display. Same for proximity sensor (which does make sense).
Maybe it is a second light sensor that is currently disabled or otherwise unavailable?
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Daniel W
post Nov 28 2019, 02:25 PM
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While I haven't yet received my Cosmo, its battery also sits under the keyboard. Planet Computers has stated they're reusing the same size and type of battery for the Cosmo, and there's nowhere else it would fit. They also need to put as much of the weight in the bottom as possible. Further, when I charge my Gemini, the top, but, thus far, not the bottom, tends to get a bit warm, even though the Gemini battery clearly is below the keyboard.

As the Gemini and, I suspect, the Cosmo, uses Pump Express + (aka 1.0), a rather primitive fast charging solution, even by 2016 standards, it can only ask the charger for 5, 7, 9 or 12 volts, and I've never seen my Gemini ask for anything but 5 or 9. Feeding 9V to a single Li-Ion cell would cause fireworks, so a DC/DC converter, making clever use of tiny capacitors to "transform" direct current, converts the voltage into what the battery needs at the moment, which changes a bit, as the battery charges. That conversion is a bit lossy, so that chip, apparently in the lid, may get noticeably warm.

For reference, Pump Express 3.0 and 4.0 can set the wall wart voltage in about 0.02V increments and can even measure the cable used, so it can ask for exactly the correct voltage at any time. That requires a more costly voltage converter in the charger (and you still need one in the phone, for 5V only chargers), but when fast charging such a device, voltage conversion losses should mostly happen in the wall wart end, not in the device being charged.

Using the app AndroSensor (just what I had on my Gemini) the small oval, with two tiny lenses, acts as a combined light and proximity sensor. Shining a bright LED onto it registers high lux readings, while covering, even when reading 0 lux, causes the proximity value to drop from 1 to 0 (the only values it knows). My readings are a bit finicky, but that might depend on the age of the app. It says both sensors are from MTK, which should mean MediaTek, so it's likely a standard sensor in their reference designs. Whether the Cosmo actually uses it, is unknown to me. I do know that the auto brightness on my Gemini is too hit and miss to be useful for me. I might sit in a dark place, but the sensor may stare right into a small overhead LED light, and think full brightness is called for. Or, if the rear of my Gemini is facing the sun, but I have a dark corridor behind me, it may drop the brightness to nothing.
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NormMonkey
post Nov 29 2019, 07:17 AM
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QUOTE(Daniel W @ Nov 28 2019, 05:25 PM) *
As the Gemini and, I suspect, the Cosmo, uses Pump Express + (aka 1.0), a rather primitive fast charging solution, even by 2016 standards, it can only ask the charger for 5, 7, 9 or 12 volts, and I've never seen my Gemini ask for anything but 5 or 9. Feeding 9V to a single Li-Ion cell would cause fireworks, so a DC/DC converter, making clever use of tiny capacitors to "transform" direct current, converts the voltage into what the battery needs at the moment, which changes a bit, as the battery charges. That conversion is a bit lossy, so that chip, apparently in the lid, may get noticeably warm.

Thanks @Daniel, that is a great explanation.

It doesn't make sense to me to have the power come in at the USB-C on the bottom, route to the top for conversion and then route to the bottom again for the power cell. Especially on the way back down, it would be a lower voltage and higher current, which I can't imagine is all that awesome across the little flex cable.


But it doesn't have to make sense to be true. Good to know that's how it is for the Gemini too. I'm a Planet newbie, this Cosmo is my first Planet device. This hardware is fantastic and I wait with 'bated breath for a Linux partition.


QUOTE(Daniel W @ Nov 28 2019, 05:25 PM) *
Using the app AndroSensor (just what I had on my Gemini) the small oval, with two tiny lenses, acts as a combined light and proximity sensor. Shining a bright LED onto it registers high lux readings, while covering, even when reading 0 lux, causes the proximity value to drop from 1 to 0 (the only values it knows). My readings are a bit finicky, but that might depend on the age of the app. It says both sensors are from MTK, which should mean MediaTek, so it's likely a standard sensor in their reference designs. Whether the Cosmo actually uses it, is unknown to me. I do know that the auto brightness on my Gemini is too hit and miss to be useful for me. I might sit in a dark place, but the sensor may stare right into a small overhead LED light, and think full brightness is called for. Or, if the rear of my Gemini is facing the sun, but I have a dark corridor behind me, it may drop the brightness to nothing.


Huh. When I shine a bright LED on the one to the right of the main screen on my Cosmo, I cannot see the two tiny lenses. However, I see exactly that when I look at the spot between the camera and the cover display. I get the same results you describe from AndroSensor when I test light level and proximity on the cover sensor, but I get no response when I try on the one to the right of the main screen.

My guess is that they're using the exact same screen /assembly as for the Gemini so the cut-out is there, but the PCB doesn't include the sensors. I suspect it's a combo sensor with both brightness and proximity in one component, and the proximity sensor needs to be on the front so that's where they put it.


I tried Adaptive Brightness but I quickly turned it off. It reacts to light changes in front of me instead of behind me. If I'm standing under a bright light and holding it main screen up, the brightness should increase so I can see despite the bright light above, but it doesn't because the ground is dark. Likewise if I'm sitting in a reclining chair and holding the thing with the front facing forward, the brightness changes depending how I sit, even though the conditions behind me are pretty constant.
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Robert
post Dec 14 2019, 06:24 PM
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QUOTE(Daniel W @ Nov 28 2019, 05:25 PM) *
While I haven't yet received my Cosmo, its battery also sits under the keyboard. Planet Computers has stated they're reusing the same size and type of battery for the Cosmo, and there's nowhere else it would fit. They also need to put as much of the weight in the bottom as possible. Further, when I charge my Gemini, the top, but, thus far, not the bottom, tends to get a bit warm, even though the Gemini battery clearly is below the keyboard.

As the Gemini and, I suspect, the Cosmo, uses Pump Express + (aka 1.0), a rather primitive fast charging solution, even by 2016 standards, it can only ask the charger for 5, 7, 9 or 12 volts, and I've never seen my Gemini ask for anything but 5 or 9. Feeding 9V to a single Li-Ion cell would cause fireworks, so a DC/DC converter, making clever use of tiny capacitors to "transform" direct current, converts the voltage into what the battery needs at the moment, which changes a bit, as the battery charges. That conversion is a bit lossy, so that chip, apparently in the lid, may get noticeably warm.

For reference, Pump Express 3.0 and 4.0 can set the wall wart voltage in about 0.02V increments and can even measure the cable used, so it can ask for exactly the correct voltage at any time. That requires a more costly voltage converter in the charger (and you still need one in the phone, for 5V only chargers), but when fast charging such a device, voltage conversion losses should mostly happen in the wall wart end, not in the device being charged.

Using the app AndroSensor (just what I had on my Gemini) the small oval, with two tiny lenses, acts as a combined light and proximity sensor. Shining a bright LED onto it registers high lux readings, while covering, even when reading 0 lux, causes the proximity value to drop from 1 to 0 (the only values it knows). My readings are a bit finicky, but that might depend on the age of the app. It says both sensors are from MTK, which should mean MediaTek, so it's likely a standard sensor in their reference designs. Whether the Cosmo actually uses it, is unknown to me. I do know that the auto brightness on my Gemini is too hit and miss to be useful for me. I might sit in a dark place, but the sensor may stare right into a small overhead LED light, and think full brightness is called for. Or, if the rear of my Gemini is facing the sun, but I have a dark corridor behind me, it may drop the brightness to nothing.


This is really a separate topic, but from the above I bet you know the answer: What type of charger should I buy (yes, I can usehe stock charger, but I also want a car charger, and probably a multiport-charger....)? This is my first device with USB>2 charging, so I haven't had to learn about this yet, and what I read is confusing.

I don't see any chargers for sale advertising compatibility with Pump Express. They are all either QC or USB-PD. Are either or both of these compatible with Pump Express? Do I just have to match volts and amps? How do I know if the Cosmo can negotiate the volts and amps it wants with the charger?

Thanks!


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Daniel W
post Dec 15 2019, 09:45 AM
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QUOTE(Robert @ Dec 15 2019, 03:24 AM) *
This is really a separate topic, but from the above I bet you know the answer: What type of charger should I buy (yes, I can use the stock charger, but I also want a car charger, and probably a multiport-charger....)? This is my first device with USB>2 charging, so I haven't had to learn about this yet, and what I read is confusing. I don't see any chargers for sale advertising compatibility with Pump Express. They are all either QC or USB-PD. Are either or both of these compatible with Pump Express? Do I just have to match volts and amps? How do I know if the Cosmo can negotiate the volts and amps it wants with the charger?
Thanks!

Summary: Any 5V ~2A USB charger from a reputable brand will be OK.

Details: For non-USB chargers, it's really important to match the voltage, polarity and connector, and to make sure the charger (and cable) can deliver enough current (enough Ampere). It's usually not a problem if the charger can supply more current, but there may be exceptions to that. Luckily, USB simplifies those things a bit, but adds other complexities...

Any USB charger for a car or mains power must support the original standard of 5V and 0.5A. That will work with any USB-charging smartphone, including the Cosmo, but a full charge would probably take a the whole night or more. For keeping a smartphone topped up, a basic 5V, 0.5A charger should be OK, as the phone draws very little current when its nearly fully charged.

The next step up for you, is any USB charger that can give ~2A (at 5V), because that's approximately as much current as a Gemini or Cosmo can draw, when the battery is close to empty. It's no problem if the charger can supply more current (say, 3A or 5A), as the phone will only draw as much current as it wants. It might be a good idea to check that the USB cable used can handle 2A. Otherwise it might cause a voltage drop, making the charging unnecessarily slow. Using a cable rated for more current, is totally fine, thought it might be a bit clumsier and more expensive, for, in this case, no real gain.

USB Fast Chargers that can supply more than 5V will always start at 5V and will only increase the voltage if the phone tells it to. Thus it's harmless to use a USB Fast charger supporting the wrong fast charging standard for you phone. The charger will just not understand what the phone says, and will stay at 5V.

While newer versions of fast charging standards, such as QC 4.0 (Quick Charge, created by Qualcomm - https://en.wikipedia.org/wiki/Quick_Charge) and Pump Express 3.0/4.0 (created by MediaTek) are more or less compatible with USB-PD (USB Power Delivery, the "official" standard - https://en.wikipedia.org/wiki/USB_hardware#PD), the Gemini and Cosmo uses Pump Express + (basically version 1.0), which is both old and uncommon, so unless you can find a car charger with support for Pump Express +, your next best option would be any 5V ~2A USB Charger. That's what I'm using most of the time, as it works decently with almost any phone or tablet charging via USB (laptops charging via USB, usually requires some version of USB-PD to get enough power to even begin charging).

While, at places like aliexpress, there is plenty of chargers being advertised as supporting Pump Express, BEWARE, as there's usually no certain way to tell safe, sane chargers apart from dangerous junk. Usually they doesn't specify which version of Pump Express they support, anyway, so chances are that, even if they're safe, they will be no better than a plain 5V ~2A USB charger. If, on the other hand, you can find a charger specifically supporting Pump Express + from a reputable brand, please post a link here on OESF. Best of luck.

Edit: Oh, and, if using a Pump Express + charger in the left-hand side port of a Cosmo or Gemini, it will ask for 9V at ~1.7 (when the battery is close to empty) and thus charges at around 9 x 1.7A = 15W. The Planet Computers chargers also supports, per the Pump Express + standard, 7V and 12V, but I've never seen my Gemini ask for it, and I don't think the Cosmo does either. I've heard that the right-hand port of a Cosmo only supports regular (5V) charging, and will, presumably not ask for more, regardless of charger. A Gemini won't changer at all from its right-hand port (but if I plug a charger in there, it still draws a few hundred mA, so it's doing something).
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Robert
post Dec 16 2019, 04:50 PM
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QUOTE(Daniel W @ Dec 15 2019, 12:45 PM) *
QUOTE(Robert @ Dec 15 2019, 03:24 AM) *
This is really a separate topic, but from the above I bet you know the answer: What type of charger should I buy (yes, I can use the stock charger, but I also want a car charger, and probably a multiport-charger....)? This is my first device with USB>2 charging, so I haven't had to learn about this yet, and what I read is confusing. I don't see any chargers for sale advertising compatibility with Pump Express. They are all either QC or USB-PD. Are either or both of these compatible with Pump Express? Do I just have to match volts and amps? How do I know if the Cosmo can negotiate the volts and amps it wants with the charger?
Thanks!

Summary: Any 5V ~2A USB charger from a reputable brand will be OK.

Details: For non-USB chargers, it's really important to match the voltage, polarity and connector, and to make sure the charger (and cable) can deliver enough current (enough Ampere). It's usually not a problem if the charger can supply more current, but there may be exceptions to that. Luckily, USB simplifies those things a bit, but adds other complexities...

Any USB charger for a car or mains power must support the original standard of 5V and 0.5A. That will work with any USB-charging smartphone, including the Cosmo, but a full charge would probably take a the whole night or more. For keeping a smartphone topped up, a basic 5V, 0.5A charger should be OK, as the phone draws very little current when its nearly fully charged.

The next step up for you, is any USB charger that can give ~2A (at 5V), because that's approximately as much current as a Gemini or Cosmo can draw, when the battery is close to empty. It's no problem if the charger can supply more current (say, 3A or 5A), as the phone will only draw as much current as it wants. It might be a good idea to check that the USB cable used can handle 2A. Otherwise it might cause a voltage drop, making the charging unnecessarily slow. Using a cable rated for more current, is totally fine, thought it might be a bit clumsier and more expensive, for, in this case, no real gain.

USB Fast Chargers that can supply more than 5V will always start at 5V and will only increase the voltage if the phone tells it to. Thus it's harmless to use a USB Fast charger supporting the wrong fast charging standard for you phone. The charger will just not understand what the phone says, and will stay at 5V.

While newer versions of fast charging standards, such as QC 4.0 (Quick Charge, created by Qualcomm - https://en.wikipedia.org/wiki/Quick_Charge) and Pump Express 3.0/4.0 (created by MediaTek) are more or less compatible with USB-PD (USB Power Delivery, the "official" standard - https://en.wikipedia.org/wiki/USB_hardware#PD), the Gemini and Cosmo uses Pump Express + (basically version 1.0), which is both old and uncommon, so unless you can find a car charger with support for Pump Express +, your next best option would be any 5V ~2A USB Charger. That's what I'm using most of the time, as it works decently with almost any phone or tablet charging via USB (laptops charging via USB, usually requires some version of USB-PD to get enough power to even begin charging).

While, at places like aliexpress, there is plenty of chargers being advertised as supporting Pump Express, BEWARE, as there's usually no certain way to tell safe, sane chargers apart from dangerous junk. Usually they doesn't specify which version of Pump Express they support, anyway, so chances are that, even if they're safe, they will be no better than a plain 5V ~2A USB charger. If, on the other hand, you can find a charger specifically supporting Pump Express + from a reputable brand, please post a link here on OESF. Best of luck.

Edit: Oh, and, if using a Pump Express + charger in the left-hand side port of a Cosmo or Gemini, it will ask for 9V at ~1.7 (when the battery is close to empty) and thus charges at around 9 x 1.7A = 15W. The Planet Computers chargers also supports, per the Pump Express + standard, 7V and 12V, but I've never seen my Gemini ask for it, and I don't think the Cosmo does either. I've heard that the right-hand port of a Cosmo only supports regular (5V) charging, and will, presumably not ask for more, regardless of charger. A Gemini won't changer at all from its right-hand port (but if I plug a charger in there, it still draws a few hundred mA, so it's doing something).


Thanks very much for the detailed response. It's unfortunate, but I guess I'll still with my "old" USB2 5v/2.4A charger for now. Thanks!
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ianisthewalrus
post Dec 17 2019, 09:59 AM
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https://www.amazon.com/Charmast-Smallest-Po...e/dp/B07L931FCY

That claimes "MTK PE"... no idea what version. no idea if this is a reputible brand. ijust got one. it seems nice so far and chargest the cosmo quickly. i dont think i have to tools to get the data you need though.

EDIT: Reading the manual, "Type-C and USB outputs are compatible with ...MTK PE 1.1/2.0..." and a whole lot of others. it does charge the cosmo up pretty fast... but I dont really hve anything to copare it to other than the stock charger.
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NVDSYPE
post Dec 21 2019, 03:05 AM
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I own this fast charger : https://www.aliexpress.com/item/33010081779...de96860f42a0-12 This is an original fast charger from brand Doogee which sells smartphones with Mediatek SOC's.
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Robert
post Dec 21 2019, 07:49 PM
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QUOTE(ianisthewalrus @ Dec 17 2019, 12:59 PM) *
https://www.amazon.com/Charmast-Smallest-Po...e/dp/B07L931FCY

That claimes "MTK PE"... no idea what version. no idea if this is a reputible brand. ijust got one. it seems nice so far and chargest the cosmo quickly. i dont think i have to tools to get the data you need though.

EDIT: Reading the manual, "Type-C and USB outputs are compatible with ...MTK PE 1.1/2.0..." and a whole lot of others. it does charge the cosmo up pretty fast... but I dont really hve anything to copare it to other than the stock charger.



Thanks!

Maybe I could combine that with a QC or PD car charger and "make" a PE car charger. ;-)
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NVDSYPE
post Dec 22 2019, 12:47 PM
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When I read the description on the Amazon website and on the website of the manufacturer: it support QC which means quick charging and is a property technology for Qualcomm SOC's. The CC has a Mediatek SOC. Here you a picture that both USB ports can quick charge Qualcomm SOC's: https://cdn.shopify.com/s/files/1/0016/4990...pg?v=1555590839
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gidds
post Jan 2 2020, 09:44 AM
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May be worth adding that it seems the slower you charge the battery, the longer it will last (in terms of charge cycles); high temperatures wear it out, and slow charging keeps it cool.

For what it's worth, I use an old generic (5V 0.5A) USB charger with my Gemini.  (I also find that more convenient: I plug it in when I go to bed every night, and it's always fully charged when I wake.  It's an easy habit to get into, and I never have to worry about finding a charger during the day.)  After 20 months of medium usage every day, the battery capacity hasn't changed noticeably.

So in the long run, if you can do that, it might not be worth finding the fastest charger, after all…
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ehem
post Jan 2 2020, 10:30 PM
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I keep wanting to find a power supply which simply provides 5V, but is high efficiency. That way I'm not worried about burning my fingers or starting a fire from a charger which generates lots of heat in a small space. Charging slow means less heat in the charger too.
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