-2

Edit: The short answer is that you cannot connect SATA to USB straightly or without a proper conversion. There are 'common' chips in market which in circuit with a transistor and couple of resistances, capacitors and diodes, do the conversion, but you must know how. This circuit can be so small that can fit inside to USB cable plug, and used by "SATA to USB" cables in markets.

The rest below was a work question.

Any portable device (such as USB or SATA etc.) must be available to do two things:

  1. Must feed its circuit with Power, either from the source port (eg. USB) or from any external power source (eg.battery or PSU etc.), and

  2. Must have a couple(tx+-) of 'channel | lane' (or more, depended on protocol) for 'data transfer'.

Τhe following example assumes that the correct distribution of currents from an Εxternal Power Source [PSU] has already been ensured.

In short, (simplified): As we know that we can combine the two 'data transfer' 'channels|lanes' (tx+-) of a SATA Drive into one and connect it to USB port, the simple idea is to connect it to two independent USB2 ports sitting on the same PC.

We see a lot of 'SATA to USB Cables' (not converter) in the market which some of them partially works or not, dependent on many things. Ιt is certain that the 'SATA to USB' connection by using 'just' proper CABLE can be achieved, definitely downgraded to the specs of a USB connection.

More specifically: SATA 7-Pin For DIY SATA To USBCable Wiring Diagram example

SATA Pin    SATA Signal |   USB Pin USB Signal  
1           GND         |     4         Ground  (black) <-|
2           A+          |    3          D+      (green) <-| 1st USB port
3           A-          |   2           D-      (white) <-|
4           GND         |     4         Ground <--- already *'common'
5           B+          |    3          F+          <--|
6           B-          |   2           F-          <--| 3dr USB port
7           GND         |     4         Ground      <--|
    * SATA pins 1,4,7 (GND) are 'common' 'shorted'

SATA 5V  (red)      to      USB 5V  (red)
SATA GND (black)    to      USB GND (black)
SATA D-  (green)    to      USB D-  (white)*
SATA D+  (white)*   to      USB D+  (green)

The work question is if is it possible to 'send' the example given SATA's:

  • A+- 'lane set' to one USB port, (eg.1st port) and…
  • B+- 'lane set' to other USB port of the same PC's USB group ports (eg.3rd port).

Very important prerequisite: Assumed that the correct distribution of currents (and voltages) from a proper Εxternal Power Source [PSU] has already been ensured for the SATA Drive (eg.HDD) Power.

Edit: answers-apology:
This idea comes as part of another 'project': [DIY] Making a USB-GamesConsole-storage for game-backups, using stock or old parts (such as HDDs and PC Power Supply), so to use my old HDDs for this. (just for fun and experiment)
As I can understand, I cannot 'play' with 'mixing those "lanes"' but I wondering If all those 'SATA to USB Cable' (Cable, NOT Converter) sellers are scammers.


I will come back to this article after the experiments.

Sorry for my bad English. Sorry for the lack of correct terminology.

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  • 2
    …maybe, but: Why. Just get the proper cable for your use case.
    – Daniel B
    Commented Mar 16 at 13:00
  • 3
    At the risk of sounding a little rude - the language and terminology is less an issue than the fundamental premise of the question
    – Journeyman Geek
    Commented Mar 16 at 13:42
  • 1
    Why the downvote? Question is a logical one that's based on logic - simply because the OP doesn't realize there's a communication language difference doesn't make it a bad question; to the contrary, that's how we learn - by being wrong
    – JW0914
    Commented Mar 16 at 14:11

2 Answers 2

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The short answer is "no", and the question is founded on incorrect assumptions.

as we know that we can combine the two 'data transfer' 'channels|lanes' (tx+-) of a SATA Drive into one and connect it to USB port,

No, that's not true to begin with. The various "USB to SATA" adapters don't do anything like that. They terminate both the USB and SATA connections internally, handling USB requests from the host and issuing their own SATA requests to the disk.

If you did literally connect a SATA device to a USB host controller, it would not be detected in any way: they differ at the physical layer (SATA runs at 1.5/3.0/6.0 Gbps, while USB2 runs at 480 Mbps; SATA uses 8b/10b while USB2 uses NRZ – although USB3 uses 8b/10b), they differ at the link layer (SATA packet headers have nothing in common with USB packet headers), and at all higher layers as well (the enumeration mechanisms are different, addressing works differently, etc. – the requests sent via USB aren't just forwarded to the SATA side).

Even the higher-layer protocols are different – SATA drives speak ATA, of course, but a USB "Mass Storage" device cannot do that; it must speak SCSI. So on top of everything else, the 'adapter' even does SCSI-ATA translation for the individual read/write/etc requests.

Literally the only thing the two connections have in common is that both of them use differential serial links; that's pretty much it.

(Even the eSATAp "dual eSATA+USB" ports that used to be present on PCs don't try to do this; they have two separate sets of pins for USB D± and SATA A±/B±, which should probably show that it's not really feasible to just connect one to the other.)

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  • Thank you! that's an in-depth review on the subject (maybe further). I'm sure you know for what you're talking about. Do you think that those who sold eg. 'SATA to USB3' CABLES are in fact scammers?
    – AntonyMan
    Commented Mar 16 at 15:23
  • However, I reserve the right, if the correct short answer is 'usually no, but under certain conditions, it might work at degraded speeds.'
    – AntonyMan
    Commented Mar 16 at 16:34
  • 2
    No, it's just that the chips have gotten so tiny they hide them inside the casing of the cables
    – Journeyman Geek
    Commented Mar 16 at 23:12
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as we know that we can combine the two 'data transfer' 'channels|lanes' (tx+-) of a SATA Drive into one and connect it to USB port, the simple idea is to connect it to two independed USB2 ports sitting on the same PC.

No because USB isn't SATA and as far as I know while chips to convert SATA to connect to a USB port are tiny, there's no chip that translates things that way

Its almost like if you had someone trying to explain theoretical physics to me in aramic. There's words coming out of the other person's mouth, but I don't understand them.

Likewise you can't just connect something communicating in one protocol (SATA) to another (USB) without something speaking something both sides understand. There's bridges that will connect a USB host to a sata drive, but not the other one.

These protocols are distinct in terms of signalling, voltages, error correction and such.

Practically at best, nothing will happen. At worst, the magic smoke escapes from something.

Basically this isn't how this works. This isn't how any of this works. You can't just wire up 2 arbitrary ports cause they both are called 'Serial' and somehow magically expect them to work.

Your Sata port is connected to a sata controller. USB ports are connected to USB controllers these translate PCIe to their respective protocols. For what you want to do to work, you'd need to somehow reprogram a sata controller to speak USB

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