Pictures for the weekend

[TrashyMG]

What happens when we get a SOC that integrates the USB super speed pin switching required by the type-C connector? Does the SOC connector pinout support 8 wires for the 4 differential pairs associated with the USB type-C connector?

I suppose it doesn't use that feature, or by the time that becomes a requirement the Pyra 2 becomes a thing.

 

[Grench]

What happens when we get a SOC that integrates the USB super speed pin switching required by the type-C connector? Does the SOC connector pinout support 8 wires for the 4 differential pairs associated with the USB type-C connector?

I suppose it doesn't use that feature, or by the time that becomes a requirement the Pyra 2 becomes a thing.

Agreed.  

Right now we're in a USB 3.0 OTG + 2 USB 2.0 port world with the Pyra - and that is fantastic.  The Pyra will have a real OS in a handheld device with the capability to haul around a terabyte of fast local storage and connect to just about any peripheral we can buy.  For 2015, the Pyra is -perfect-.  It may even get an SoC update somewhere in it's life spawn of 3-5 years.

The Pyra's successor (P3?), though, I could see as a bit different in port configuration.  Keep in mind we're talking about somewhere around year 2018-2020 here.  The Pyra has sockets for audio, charging/serial, usb2, usb2/esata, hdmi, usb3/OTG, 1 micro UHS-I, 2 UHS-I.   I could see a P3 having a headphone jack and 3 or 4 USB-C connectors and UHS-II card slots.

 

[Galaxis]

The question is how long eSATA will be of interest at all. I am under the impression that it becomes already difficult to find devices with external eSATA.

Yeah... A year makes quite a difference. By now, full-size SD-Card slots don't look preferable anymore, either - microSD is everywhere...

 

[EvilDragon]

MicroSD is stuck at 200GB right now, they can't even reach 256GB, whereas normal sized SDs are at 512 GB already.


Sent from my Nexus 7 using Tapatalk

 

[Binky]

The question is how long eSATA will be of interest at all. I am under the impression that it becomes already difficult to find devices with external eSATA.

Yeah... A year makes quite a difference. By now, full-size SD-Card slots don't look preferable anymore, either - microSD is everywhere...

cue joke about miniSD?

Seriously though, this comment has been brought up frequently for the last few years.

• By simple virtue of volume, a fullSD card will always be able to store more data.
• fullSD(HC,XC) cards are still readily available and undergoing development by major manufacturers.
• Most cameras and camcorders use fullSD cards.
• This community has shown a preference for fullSD cards, and lots of them.
• Adaptors to use µSD cards with fullSD slots are cheap and unobtrustive
• the Pyra is not a device to skimp much on functionality in favour of size

Why would µSD be preferable?

 

[ssokolow]

The question is how long eSATA will be of interest at all.

It's irrelevant, there's no practical (speed) benefit to using an eSATA harddrive vs a USB3.0 one. Once we've got the capability of dedicated USB3.0 host you can ditch the eSATA port.

My own experience shows that SATA is still lighter on the CPU than USB 3... which disproves your "no practical speed benefit" statement.

Also, eSATA pretty much guarantees S.M.A.R.T. support while, with USB 3, it's a vendor-specificity crapshoot. As such, I only use USB 3 drives for stuff I've already backed up and don't mind losing without warning. (eg. I have all my games on a USB 3 drive and I've used symlink trickery, chmod, and chown to ensure that the less spec-compliant ones can't store any volatile data outside $HOME)

 

[WizardStan]

Point taken. I suspect the CPU wouldn't be a bottleneck and by the time such a thing comes around any difference would probably be so minor as to be ignorable but only time will tell there.

The SMART support is definitely valid though. An interesting proposal now.

 

[Silent-Hunter]

Too bad there isn't room for a CompactFlash slot! I've seen VERY fast CF cards, way faster than the fastest SD cards.

 

[WizardStan]

Unfortunately the OMAP5 doesn't have CF pins else I might think you were being serious

 

[Slacker]

By now, full-size SD-Card slots don't look preferable anymore, either - microSD is everywhere...

µSD cards might be everywhere, but they are SLOW, especially at random access IOPS. You can buy an expensive full-SD card that reaches spinning-platter HDD levels of performance. Good luck finding an µSD card that's less than 20x slower...


You're fine storing bulk data on such cards, but you really want those IOPS for a system drive...

 

[levi]

Ironically, the MicroSD card slot the Pyra will have, designed to mask the on-board NAND flash if present is designed to install the system/OS to (should the NAND break, or you just choose not to use up its write cycles).  But the swift seek times of solid state storage compared to spinning platters should mean it still boots pretty smartish, even if the bandwidth isn't there.

 

[Letalis Sonus]

Unfortunately the OMAP5 doesn't have CF pins else I might think you were being serious

Well, actually... CF has always been directly derived from what is common in a full featured PC, classic CF actually uses a traditional IDE interface and the newer CFast standard simply uses SATA.The eSATA port could really have been used to provide a CFast slot instead.

 

[Neelix]

Yeah... A year makes quite a difference. By now, full-size SD-Card slots don't look preferable anymore, either - microSD is everywhere...

MicroSD cards can be used in a full-size SD card slot via an adapter. Using a micro-SD slot to read a full sized SD card on the other hand...

Just because microSD is common is no reason to exclude the ability to read full sized SD cards as a feature.

- Neelix

 

[Illuminerdi]

To use a type-C connector will require a little bit more than just the connector. The type-C cable has 4 differential pairs for super speed instead of the old cables 2 pairs. The device connects to two of them, but since the connector is reversible, the host must determine which pairs are in use and switch to those pairs. Since this capability is not yet built into existing ICs, an additional IC must be added to do the switching. If you are lucky, this function is included in the IC that does charger detection/ battery charging etc.

One of the other "features" of the type C connector is that it can be used to connect headsets. Unfortunately they screwed this up. Current headsets do LRGM, or LRMG depending on if you got your headset in the US, or in Europe. (L=left, R=Right, M= microphone, and G= GROUND).

A bit of background: Using a three wire connection for earphones was a bad idea. Sharing the ground return wire causes cross talk because of the resistance of the wire. This can be mitigated my running 4 wires in the headset cable, and tying the return wires from the left & right speakers together in the connector. The drive circuit must also use kelvin sensing directly on the GND pin of the headphone jack and feed that back to the amplifiers to minimize the cross talk.

When they add the additional mic connection, you are ok as long as you only use one of the two types of headsets.

If you want to design your system to detect the type of the headset, and automatically swap GND and mic signals, you compromise your crosstalk numbers because you must now run the GND line through a switch, and switches have higher resistance than wires. Worse, the switch is usually a FET which has a resistance that varies with the voltage between its gate and the signal. This adds harmonic distortion.

The type C connector can be plugged in either way. The way the audio is wired, it swapps the GND & mic signals when you swap the way you plug in the cable. Therefore, on top of the switch you need to switch between audio & USB3 signals, you also need a switch to be able to swap GND and mic.

This is really annoying because with 28 pins, they could easily have run differential signals to each speaker, and the mic, giving a jack that would have performed better than the existing 3 pin headphone jack. Running the signals differentially eliminates most of the problems caused by the switches.

Thanks for the explanation - I too was wondering about the differences between Type B and C.  Personally though, I still prefer Type C.  Yes - audio quality may be impacted due to the aforementioned crosstalk/distortion potential because of the limited available wire pairs, but ultimately I don't really want/need amazing sound quality from pretty much any device of mine that would use USB Type C.  Good sound needs good headphones, and good headphones are rarely very "portable", so ultimately to me the expectation of good sound from a "portable" device like the Pyra is in conflict with that.  Besides, if I was really worried about sound quality I could always connect a good pair of Bluetooth headphones to it instead, eliminating the wire as a source of interference entirely.

But this is just my opinion - YMMV.

 

[Hồng Thất Công]

Yeah... A year makes quite a difference. By now, full-size SD-Card slots don't look preferable anymore, either - microSD is everywhere...

MicroSD cards can be used in a full-size SD card slot via an adapter. Using a micro-SD slot to read a full sized SD card on the other hand...

Spoiler

But yeah, keep the standard SD card slots for Pyra please.

 

[Kiga]

Nice to have a future-proof USB3 port, even though the currently only CPU board can't handle it. It will lead to confusion though, with people expecting USB3 speeds and only getting USB2.

Is there a way to include a USB3 hub on the CPU board so both the micro-USB3 and the full-size USB3 port can actually achieve USB3 speeds? (though not both at the same time, since there would of course still be only one connection to the OMAP5)

That would be the most awesome solution, but I guess it is not possible to do something like that...

A black USB3 port would solve this issue. Anyway I don't want a flashy blue port on my Pyra just to show that there is USB3. It's useless, bling-bling and ugly.

 

 

[WizardStan]

The eSATA port could really have been used to provide a CFast slot instead.

Oh wow, I did not know that, never heard of CFast. I'd kind of assumed CompactFlash was dead. I spent weeks tracking down a CF card for my mom's embroidery machine few years ago, one that wouldn't cost a bajillion dollars. Obviously not "dead", but seemed like they were on the way out.

 

[Slacker]

Ironically, the MicroSD card slot the Pyra will have, designed to mask the on-board NAND flash if present is designed to install the system/OS to (should the NAND break, or you just choose not to use up its write cycles).  But the swift seek times of solid state storage compared to spinning platters should mean it still boots pretty smartish, even if the bandwidth isn't there.

Not so swift without a good controller and proper die-level parallelism to exploit.


That's why you'd rather use the built-in eMMC if possible. Those things are designed to be used as system drives and have tolerable random-access speeds (often better than any SD card).

Good sound needs good headphones, and good headphones are rarely very "portable", so ultimately to me the expectation of good sound from a "portable" device like the Pyra is in conflict with that.

You'd be surprised, there are some really good in-ear monitors on the market. Golden-eared audiophile grade good.

Besides, if I was really worried about sound quality I could always connect a good pair of Bluetooth headphones to it instead, eliminating the wire as a source of interference entirely.

Bluetooth has limited bandwidth and uses lossy compression to fit the signal within it. You'll lose more fidelity that way than through any shitty connector or cable.

 

[levi]

I boot my Pandora OS off a Sandisk Etreme card, and it boots in a similar time to it takes to boot off NAND/eMMC on that.  It's fast enough for me.

The eSATA port could really have been used to provide a CFast slot instead.

Oh wow, I did not know that, never heard of CFast. I'd kind of assumed CompactFlash was dead. I spent weeks tracking down a CF card for my mom's embroidery machine few years ago, one that wouldn't cost a bajillion dollars. Obviously not "dead", but seemed like they were on the way out.

I've just done a search for CFast cards.  Ouch!  Assuming you'd only fit on CF slot on the front of a Pyra it would limit us to 256GB based on what's currently on the market.  Perhaps more of a concern is the price - even that 256GB is over 3 GBP per GB, whereas even high quality SD cards top out at about 1GBP per GB.

CFast does seem to have found a fairly healthy niche though - there are still a number of brands out there, but it seems to specialise in smaller but insanely fast cards.  Not a good fit for the Pyra though really.

 

[Glyph Reader]

You'd be surprised, there are some really good in-ear monitors on the market. Golden-eared audiophile grade good.

 

Really?  Could you link to some?

-Glyph Reader