Memory Poll on Pyra

How much RAM do you want?

  • 1GB (or less)

    Votes: 0 0.0%
  • 2GB

    Votes: 59 50.4%
  • 4GB

    Votes: 48 41.0%
  • 8GB

    Votes: 7 6.0%
  • 12GB (or more)

    Votes: 3 2.6%

  • Total voters
    117

This UHS-II SD through SATA idea needs to be explored; even if we don't want it for the internal storage, it could be good to have it on one of the external SD slots. The speed of the SD slots is likely to become the limiting factor on the Pyra (like it was on the Pandora too) since cards already exist today that are faster than that. So it would be really nice if we can get a potential factor 3 speedup in this way.
If you're going to give SD on SATA serious consideration, then take a 2nd look at: http://www.d-broad.com/db300_eg.html


It can run TWO SD ports to the SATA connector. I.e. you could link both of the front SD ports to the SATA controller.


Booting off of an internal eMMC or microSD, those front facing ports could scream. They would still be mount/unmount capable - the system would simply see them as if they were removable hard drives.


Then we get into the hacker-fun territory. That bridge controller is also RAID capable. If someone chose to they could put two SDXC cards in, set the controller to RAID 0 or 1 and have a darn fast or failure protected 'desktop' machine. Not advisable for 'normal' users, but it'd be kind of cool 'just to do'.


I think it's still in the 'hold my beer and check this out' territory. We don't know how much work or space would be required to implement a http://www.d-broad.com/db300_eg.html type solution. The control chip is very tiny - but I'm not sure what else on their dev board would be required in a Pyra.


Still - the thought of having two front facing 200+MB/s SD ports gives me chills.
That link only has UHS-I (max 100MB/s per SD card) and 150MB/s SATA though. But I like the idea.
 
This UHS-II SD through SATA idea needs to be explored; even if we don't want it for the internal storage, it could be good to have it on one of the external SD slots. The speed of the SD slots is likely to become the limiting factor on the Pyra (like it was on the Pandora too) since cards already exist today that are faster than that. So it would be really nice if we can get a potential factor 3 speedup in this way.
If you're going to give SD on SATA serious consideration, then take a 2nd look at: http://www.d-broad.com/db300_eg.html

It can run TWO SD ports to the SATA connector. I.e. you could link both of the front SD ports to the SATA controller.

Booting off of an internal eMMC or microSD, those front facing ports could scream. They would still be mount/unmount capable - the system would simply see them as if they were removable hard drives.

Then we get into the hacker-fun territory. That bridge controller is also RAID capable. If someone chose to they could put two SDXC cards in, set the controller to RAID 0 or 1 and have a darn fast or failure protected 'desktop' machine. Not advisable for 'normal' users, but it'd be kind of cool 'just to do'.

I think it's still in the 'hold my beer and check this out' territory. We don't know how much work or space would be required to implement a http://www.d-broad.com/db300_eg.html type solution. The control chip is very tiny - but I'm not sure what else on their dev board would be required in a Pyra.

Still - the thought of having two front facing 200+MB/s SD ports gives me chills.
 That link only has UHS-I (max 100MB/s per SD card) and 150MB/s SATA though. But I like the idea.
You're right. Those UHS-2 cards are a whole different animal with an additional set of pins. I believe that makes them 'out of scope' for the Pyra.

At 100MB/s per SD card - that SATA alternative really isn't actually faster than the SD interface on the OMAP, right? It appears to all come down to the SDR104 spec. Will the SD interface on the OMAP support SDR104 SD (micro and/or full size) media?

Still 5 times the speed of the SD slots on the Pandora. I'll take it either way.
 
It can run TWO SD ports to the SATA connector
The SATA port on the OMAP5 is bootable, as is two of the four MMC ports (eg, the eMMC and presumably the left SD slot).If this SATA->SD adapter is used, would it still be bootable I wonder? Would both SD slots be bootable via SATA or would only the first?

It's an interesting idea but I get the feeling that it might not be possible to boot from it (or maybe you can, it's hard to tell how it would behave) and if not then it wouldn't be a good idea.
 
This UHS-II SD through SATA idea needs to be explored; even if we don't want it for the internal storage, it could be good to have it on one of the external SD slots. The speed of the SD slots is likely to become the limiting factor on the Pyra (like it was on the Pandora too) since cards already exist today that are faster than that. So it would be really nice if we can get a potential factor 3 speedup in this way.
If you're going to give SD on SATA serious consideration, then take a 2nd look at: http://www.d-broad.com/db300_eg.html


It can run TWO SD ports to the SATA connector. I.e. you could link both of the front SD ports to the SATA controller.


Booting off of an internal eMMC or microSD, those front facing ports could scream. They would still be mount/unmount capable - the system would simply see them as if they were removable hard drives.


Then we get into the hacker-fun territory. That bridge controller is also RAID capable. If someone chose to they could put two SDXC cards in, set the controller to RAID 0 or 1 and have a darn fast or failure protected 'desktop' machine. Not advisable for 'normal' users, but it'd be kind of cool 'just to do'.


I think it's still in the 'hold my beer and check this out' territory. We don't know how much work or space would be required to implement a http://www.d-broad.com/db300_eg.html type solution. The control chip is very tiny - but I'm not sure what else on their dev board would be required in a Pyra.


Still - the thought of having two front facing 200+MB/s SD ports gives me chills.
 
That link only has UHS-I (max 100MB/s per SD card) and 150MB/s SATA though. But I like the idea.
You're right. Those UHS-2 cards are a whole different animal with an additional set of pins. I believe that makes them 'out of scope' for the Pyra.


At 100MB/s per SD card - that SATA alternative really isn't actually faster than the SD interface on the OMAP, right? It appears to all come down to the SDR104 spec. Will the SD interface on the OMAP support SDR104 SD (micro and/or full size) media?


Still 5 times the speed of the SD slots on the Pandora. I'll take it either way.
Yes, both this DB300 and the OMAP5432 can deal with SDR104. The only reason for taking that SATA detour is to have 4 SD/eMMC storage devices instead of 3.

I wonder if something similar but more advanced exists that can read HD312 UHS-II SD cards at 312MB/s and convert it to SATA 2.0 at 3Gbit/s (300MB/s) -- the OMAP5432 can handle that SATA speed.
 
I'm not sure UHS-II is a good idea - is it fully backwards compatible? Because in the next few years, most would continue to use normal SD unless they want to pay insane amounts.

I think that 2SD - SATA adaptor or even one which supports only one SD would be good.

But... considering the price, I'm still for uSD and no eMMC. uSD can be fast enough, uSD's sizes fit everyone and it's the cheapest solution.
 
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My preference would would be

1) eMMC for the OS

2) 2 SD slots -  

     1 Normal SD card slot

     2 UHS-II SD Card slot (via SATA?) - so that we have a future proof option to use these faster cards in the future.  Currently they are way to expensive - $400 for a 32GB UHS-II card.   I'm also concerned about there minimum power draw when operating, the SD datasheet says UHS-II host requires a minimum of .72W , I'm guessing idle is way lower , but if it needs that as a minimum  to operate when doing reads/writes its worth a note.  However, if we leave the other SD slot as normal, we should then have a low power option.  Maybe Exophase can make more sense out of the datasheet (see page 21)  https://docs.google.com/viewer?url=https://www.sdcard.org/downloads/pls/simplified_specs/part1_410.pdf

3) If its then possible to add a SIM/uSB combo, then go for it
 
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16gb is fine. I will be pissed if it switches to micro SD external memory though.


I paid a lot for my 128 GB cards plus when you remove cards a lot like I do from my Pandora to laptop fiddling about with an expensive but tiny card is far more dangerous than the 'cart' sized SD cards.
 
16gb is fine. I will be pissed if it switches to micro SD external memory though.

I paid a lot for my 128 GB cards plus when you remove cards a lot like I do from my Pandora to laptop fiddling about with an expensive but tiny card is far more dangerous than the 'cart' sized SD cards.
The debate is between a 16GB eMMC module and a 16GB uSD card for the INTERNAL boot 'disk'.

From the example board shown, the two external facing SD card slots are still planned as full sized SDXC.
 
4G only makes the 2G voters happy if it doesn't remove a feature that might be more important to them than the 2nd 2G. Like price, second SD card slot, speed, separate chargin jack, power consumption, whatever.
 
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