Apple iPod Shuffle USB interface pinout
pinoutguide.com
pinoutguide.com
[0] https://keeb.io/products/trrs-cable
[1] https://docs.splitkb.com/hc/en-us/articles/360010443660-Kyri...
[2] https://www.kingcables.org/products/custom-straight-usb-cabl...
There is a note about a diode across VCC and GND — perhaps that is to prevent this kind of short?
Even from the power consumer side, there is a chance that a single female side contact (eg VCC) may touch two adjacent TRRS sections as the plug is being removed.
So lets imagine what happens to the host port when you unplug a live device. Vcc breaks first, and all other pins shift. D+ and D- are safe to short together or to ground (and I'm pretty sure safe to short to Vcc) so they don't matter much. The shield is physically out of the socket. As the connectors move, you get connections that put Vcc on the device's Data pins, through the device ground to host Data pins. This is equivalent to a large resistor between host Vcc and data pins, which is safe.
As the connector is removed, the device's ground contacts host's Vcc. Nothing happens because all the other pins are physically outside of the socket. There is no circuit, no path for the current to go. The only way it could be a problem is if the device had some external ground connection. That would create a direct short between the host's Vcc and ground.
But (correctly implemented) USB ports can safely tolerate a short from Vcc to ground. If not, it's not complicated or expensive to build protection into the device.
Even if all of the above weren't true, it's still not complicated or expensive to design a port which is tolerant to any kind of short on any pins.
What you're arguing is both not possible and wouldn't be a problem even if it were.
If you shove data in the middle, you're never going to short VCC + GND together. your data line shouldn't care about being high (5v) or low (gnd).
You only turn on actual power when it is firmly connected and you turn it off immediately when there is any signal that it might be disconnecting.
Having to add a bunch of components to implement such a feature isn't really worth it when switching to USB-C also solves the problem, at basically zero cost and effort. It's not spec-compliant of course, but who cares with DIY?
It usually makes more sense to just stick a Pro Micro on each side, and have them talk serial over TRRS. As a bonus, you can connect it to your PC from either half.
it's a good reliable plug if you can cram what you need through it, I can kind of understand why people gravitate towards it in design.
Recently I found myself in the market for a custom keyboard, to my great surprise. Custom as not as DIY but as something different than $10 OTC or even $100 Logitech.
After the hours of watching pics I decided to just see it with my own hands and went to a shop which specialize on them.
And there I confirmed the feeling what I had before - 99% of these keyboards, despite quite advanced tech gone into them on all layers, are not usable, because they are made to stroke the ego of the owner but not for the actual work. This is especially evident by the crammed right cluster which makes typing brackets, curlies and quotes quite a pain, because the Shift key is gutted and nowhere under the right pinky.
Using something else than microUSB or Type-C (for the PC connector) is just a cherry on top.
Despite pushing the envelope in many ways, custom keyboards can also be strangely traditionalist at the same time. Making a PCB is a risky venture and most manufacturers don't want to risk it.
A huge amount of models still use a huge 7u or larger space bar for example when something as small as 4u would suffice, and leave room for much more ergonomic placement of modifiers. (or other improvements like extra keys, keyed gaps etc.)
There's a very good chance that the above poster was looking at staggered layouts if it's their first foray into custom keyboards, and not even considering orthos.
Come up with your own layout and get that custom design made.
Ah, yes, just searching for the wide RShift, on the place where it was for the last 30 years is 'customized for me'. K TNX
https://ipod-shuffle-manager.en.lo4d.com/windows
Heikki Ylinen's iPod Shuffle Manager, for the unaware, is a portable 12k app that sits on the root of an iPod shuffle. When you launch it, it scans the entire stick for MP3 files, then builds a compatible iPod shuffle database and shoves it where it needs to go so the Shuffle just acts like a dumb MP3 player without iTunes.
I personally prefer the iPod Nano 7th gen, which is great in terms of usability, has bluetooth 4.0 and is also very small size. Repair is a nightmare though and finding an affordable but still working device is not that easy.
If smallest size is not a requirement, you could go for the HiBy M300 - a pretty new Android 13 device supporting most Apps, 2TB of microSD Storage, having control buttons and also cable headphone remote support (OMTP, not CTIA), but still not that big.
Maybe a modified Apple iPod Classic 2009 with an iFlash Quad and 2000mah battery also fits your needs. It's way bigger than a shuffle, but it's at least maintainable (battery and storage replacement).
Apple did a really great job on remote controlling the devices with "tap"-Codes (tap, double tap, triple tap). The iPod Classic 2009 for example does not support the codes for fast forward / rewind (tap+tap_hold=ff, tap,tap,tap_hold=r). That's something I regularly use for audiobooks, so I'm tied to the iPod Nano 7g (the 6g would also work, but I prefer the larger display for navigating chapters).
There are android devices supporting these tap codes partially, but not as good / reliable as the iPod Nano 7g. Android also is using OMTP while Apple is using CTIA, so Apple headphones won't work on android and vice versa. CTIA=>OMTP Adapters (from amazon) just switch the pinout, which does not work, because Apple uses different Resistance on the Pinout.
I also "modded" one of my iPod Nano 7g by partially milling out the aluminium backplate and soldering in an iPod Mini battery (600mah), so that I got nearly 3 times the battery life of a factory iPod Nano as well as an easy to replace battery without opening the device (which is way to hard). The bigger iPod Mini battery does not fit without a silicone bumper, but since I already used one, it was perfectly fine. Changing the battery still requires soldering, but at least not fiddling with the very fragile display removal procedure.
However, currently I did not find a better device for my use case than the iPod Nano 7g. And everything is better with bluetooth... although I don't use it :-)
Older Androids used OMTP but they eventually standardised on CTIA too:
https://source.android.com/docs/core/interaction/accessories...
https://www.dhgate.com/product/m13-bluetooth-mp3-player-mini...
I can easily see myself buying one of those, adding a 512Gb uSD card on it and ditch Spotify.
I had one of the USB-via-TRRS models that this post is about and really liked it for running. Had a built-in clip so you could attach it to your waistband.
One problem with using TRRS for USB is that Vbus can be short-circuited while plugging and unplugging; the clones of the 2nd generation Shuffle tended to use a regular mini-USB instead, which offers the advantage that it can be charged while listening: http://tarkus-notes.com/en/chinese-mp3-player-ipod-shuffle-c...
The hobbyist ergonomic keyboard community has used TRRS for the link between the left and right half of the keyboard for a while now, and it routinely causes issue due to people accidentally unplugging it while powered - which fries their keyboard.
I totally expect the 3.5mm Toslink plug to come back once we inevitable switch over to fiber, though!
But phone connectors have built-in switches, so I would think there must be some configuration to route the powered lines through the switches so that the power is only connected until the plug is fully inserted, I think. For instance, if insertion of the tip control a double-pole double-throw switch, then one of those could route the ground pin and one could route the power pin, such that those power lines are only routed once full insertion has been made.
I believe that someone has had this problem, but I cannot replicate it. I unplug the right hand of my Iris all the time like a jackass and so far no ill effects. IDGI.
I love Toslink but I wouldn’t expect it on as many TVs, devices and systems as I see them
Is it just the lack of the need for DAC chips, cost, or something I’m missing?
Many TVs and devices exclude many digital and analogue sockets, but for some reason I always see Toslink
Cost: TOSLINK can be implemented with two plastic connectors (one an LED, one a photodiode). After that, you're in a 3.3V domain. Other interfaces require transformers and other analog electronics to go from the signalling domain to one that is useful in a digital system.
Noise/electrical performance: Using an optical interface means the systems are fully electrically isolated, with no risk of ground loops or noise coupling. There is also no risk of radiated emissions.
Cabling convenience: TOSLINK supports a very long, thin, cable that can be checked for functionality at a glance (look at the receiver end: is there light?). Any comparable electrical interface is going to be at least 3 conductors and require a multimeter to check for breaks.
Lastly, the reason to prefer digital is that every A/D-D/A step adds noise, distortion, and latency. The general desire is to convert to analog as late in the chain as possible to avoid that.
Alternatively, use a ring which is segmented in 120 degree pieces, and place two contacts 180 degree apart in the socket: any two ring segments might be shorted, but never all three - and there will always be at least two segments with a connection. Use a bridge rectifier to get a fixed polarity out of it.
I think TRRS USB would have resulted in people confusing them with the much more common audio connectors and confusing host and peripheral. That could have killed USB from the start.
https://en.wikipedia.org/wiki/Phone_connector_(audio)#Histor...
There is absolutely no reason why you'd need to re-invent something as silly as this and do it wrong.
That's $0.30 worth of hardware to deal with though. Of course in mass market products such amounts really matter but I feel that the convenience and reliability factor as well as consumer centric thinking should allow for that kind of expense.
You can search for "reversible USB A cable" - there are lots of them available for sale.
I assume the "USB Trident" logo is imprinted on both sides since you can plug it in either way. ;-)
It works as a hobbyist solution, but it's a long term disaster.
I was never sure if I'd need to recreate make some cable for it, or if it's battery would fail first.
But I suppose, looking back, much of my computing history is doing weird and unlikely stuff for a strange payoff, so at least I am consistent.
My hope is that I can avoid iTunes, which, on Windows, has a reputation for trashing collections willy-nilly.
I'm running my little sony walkman mp3 usb stick into the ground, but it only accepts wired in ear phones, and they tend to break a lot (and are now starting to confuse young salesman in electronics shops).
I have emailed customer support 3 times with no reply, tried Twitter and literally cannot get a response from them at all. Really really disappointing as I love(d) the product and what the company was trying to create.
https://bemighty.com/products/mighty-audio-screenless-connec...
Sleep deprived cynicism, but hardly "without a screen". Just, use without a screen.
The same measurement of resistance between the innermost two contacts is now a standard for Android in-line headset controls, although Apple's implementation used 0, 4.7k, and 10k ohms instead of Android's much lower (<1k) values.
Weird what a small place the internet is.
I break a USB cable every week just because it gets wedged between 2 standing desks, stuck in office chair, gets slammed in car door, bent by thigh while in pocket connected to device, etc.
The people who designed USB Micro-B and USB-C are probably people who sit in an office all day and never bike, ski, etc. They don't realize that "consumer grade" stuff needs to be 10X stronger than military grade. Consumers connect devices together, stuff everything in pocket with wires connected and go skiing. Military people just sit in an armchair behind bulletproof glass and fire.
Never had a 1/8" headphone jack break that way, I've dropped bricks on those things, stomped over them, biked over them, had them sucked up by vacuum cleaners and vacuum robots, chewed by pets, they've been largely fine. A 1/4" headphone jack once got wedged between two standing desks and it was strong enough that the whole desk lifted off and the cable was intact, the jack barrel alone supporting the entire 100 kg of desk with everything on it. Cable still functions perfectly. REAL consumer grade stuff.