Arduino Based Solid State Drive

Question

I've searched high and low for something to get me on the right track, it's making me think it might not be possible.

Basically, I want to create a cheap SSD using Arduino (or another microcontroller if it is too weak). I know I would have to implement the SATA protocol on the device and an OS driver for the disk drive. Assuming I could jump those two hurdles, what else would bar me from implementing a rudimentary SSD? I'm not even talking about full production quality, just a SATA wire coming from a mother board plugged into a socket on a breadboard. Do I need flash storage or would I need another kind of chip to handle the data needs?

• Eugene Sh.: Do you understand what SSD is standing for? Maybe you mean just some kind of SATA-connected storage?
• Adam Lawrence: The legacy SATA 1.0 throughput of 1.5 GB/s is going to be a huge problem without dedicated hardware - I don't think you stand a chance on any Arduino.
• John U: Is the SATA standard really not documented anywhere on the entire internet?
• Chris Stratton: If you want to do this just for fun, implement USB Mass Storage on a Leonardo backed by an SD card or SPI flash. It will be painfully slow, but the concept will be there. Outside of the Arduino realm, I expect you could find an existing project to do this with the STM32F4 Discovery board (which is cheaper anyway).
• Stephan Møller: This is such an awesome quest, Creating a storage device from scratch to be used from a computer. I really hope you succeed and please post updates if you make it :)

Answer 1

The good news is that SATA drivers are fairly generic so you don't have to write the OS side. The bad news is everything else.

just a SATA wire coming from a mother board plugged into a socket on a breadboard

Let me stop you there. The minimum data rate for SATA is sufficiently high that you need a PCB. If you try and do this with wires or breadboards it will simply not get through; it will be lost to parasitic capacitance.

(Many years ago as a student I tried to do something vaguely similar with a wire-wrap board. At just 20MHz you could see a clean signal go in one side and a noisy unreadable mess come out the other side. Actually seeing it on a scope drove home the importance of shielding.)

Do I need flash storage or would I need another kind of chip to handle the data needs

Where would you put the data otherwise? It might be an entertaining first step to create a read-only drive with constant contents, but it's not very useful.

You need a chip with a SATA interface. This will almost certainly be an ARM and almost certainly not in DIP. I can't remember at the moment whether SATA master and slave "PHY" interfaces are different or whether it's all defined in software, someone else can answer that.

• Michael Brown: Sweet thanks for the info. I guess the Arduino is a very "beginner's" setup so I would want to get a more advanced controller for such an undertaking. Thanks for the info.
• Russell McMahon: @pjc50 - He could implement a Write Only Memory - perhaps an emulation of the Signetics 9C46XN / 25120