The PiDrive is a standard-size Raspberry Pi hat that plugs directly into the 40-pin I/O connector of any Raspberry Pi B+, A+, or B+ v2. The PiDrive expansion card allows the user to install any size mSATA SSD onto the Raspberry Pi. The PiDrive expansion card has low power requirements, yet provides vastly increased performance speed for the Raspberry Pi.

Why do you need a PiDrive?

All Raspberry Pi single-board computers utilize a micro SD card as the standard, default storage system for both the operating system and user data files. The micro SD card was originally intended to store pictures, music, and other user data, and was NOT intended to be the primary storage device for computer operating systems such as LINUX. The constant demands of the operating system on the micro SD card has impacted the reliability of the micro SD storage system and can result in a frustrating loss of data and complete micro SD system failure.

The PiDrive offers a significantly faster operating speed and significantly larger storage capacity option for the Raspberry Pi. The PiDrive expansion card eliminates the need for external hard drives with messy cables, making the user’s Raspberry Pi system much more portable.

The PiDrive expansion card has a low-power requirement allowing it to be plugged directly into one of the Raspberry Pi’s USB ports, with no external powered USB hubs necessary. Because the PiDrive expansion card has low power requirements, other peripherals such as an external keyboard, wireless adapter, etc., are able to be used via the Pi’s other available USB ports at the same time, a vast improvement over unattractive external powered-USB hubs and cables sprawling all over the user’s workspace! 

Can My Pi Boot From The PiDrive?

Technically, yes. The Pi still needs the micro SD card to start the boot loader process but after a couple of seconds everything will then load from the PiDrive. There will be no need for the micro SD card until you need to reboot. You will definitely notice an improvement in boot times. Your system will typically boot in 10-20 seconds, depending on your operating system start up requirements. 

The PiDrive comes with a micro SD card pre-programmed with a boot loader and operating system installer. 

Isn't A USB Flash Drive Or SD Card The Same Thing As A PiDrive?

They are the same only in the sense that they both use similar flash memory chips and both are limited by the speed of the USB bus. 

The flash drive is made to be as small and as inexpensive as possible. Most flash drives have only one or two flash memory chips and a minimal controller to interface to the USB port. The components used in a flash drive are typically of lower performance compared to an SSD to meet lower consumer price demands. The flash drive depends on the host PC to do the read/write buffering and other tasks. This causes the flash drive to pause while it reads and writes. A flash drive and a micro SD card are both storage devices that emulate a hard disk, but the true nature of these devices is to be a simple storage medium for photos, music, files, etc. This is why the Pi's drive access time is so slow.

On the other hand, an mSATA SSD will have multiple flash memory chips and will meet higher performance standards. The mSATA SSD has an extremely sophisticated controller that supports all of the SATA interface drive specifications. An SSD provides for wear leveling, over provisioning, and other performance-enhancing algorithms. It also has read/write buffering so that it does not have to stop and decide what to do next. An mSATA SSD is a true mass storage device made to efficiently run a modern operating system.

If you are simply storing pictures and music, then all you need is a flash drive. However, if you really want to speed up your Pi, then you need a device that was designed primarily to run an operating system, not a simple file storage device such as a flash drive or micro SD card. 

The main reason that the Raspberry Pi uses a micro SD card for the operating system is the cost, as it is the only way to keep the entry level price low. The micro SD interface on the Pi is the least expensive interface option the designers had available. 

The PiDrive interfaces the Pi's USB bus to the SATA interface on the mSATA drive. This is the same way that an external USB hard drive drive enclosure works but it all fits within, and is powered by, the Pi.

An mSATA SSD on a PiDrive is easily two to four times faster than a flash drive or micro SD card. Using a PiDrive, your Pi will boot faster, programs will load faster, and disk intensive applications will be faster. 

What Do I Get With The PiDrive Board?  

• The PiDrive board (no mSATA drive) 
• Custom cable to connect the PiDrive to a Pi USB port 
• Micro SD card, pre-programmed with a custom boot loader and installer, to set up thePiDrive for the first time with an operating system

What Should I Look For In An mSATA Drive? Is Faster Better?

Normally faster is always better, but since the Pi uses a USB 2.0 interface that is about one-fifth the speed of an SSD, it does not really matter. Any mSATA SSD will be faster than the USB port, so do not waste your money on a high-performance drive.

Even though you do not need a fast SSD, you do want a quality device. After all, you are putting all of your data on the SSD so you do want a reliable drive!

Our preferred brand of mSATA SSD is the MyDigitalSSD line of mSATA drives. They are reliable devices, have very competitive prices, great support, and have very high customer satisfaction ratings.

Technical Details

The PiDrive uses the Prolific Technology Inc. PL-2571 single chip Hi-Speed USB-to-SATA bridge controller chip and is based on the Prolific's PL-2571 reference design. 

• The PiDrive is low power and only consumes 250ma under full load and 160ma in idle mode
• Includes a stack-able GPIO header
• Does not use any of the Pi GPIO pins so will not affect other hats
• The PiDrive is powered by the USB port only
• No driver installation needed in Linux (kernel 2.4.18 or above)
• Micron MLC Sync NAND Flash  
• PHISON S8 Controller  
• Withstand extreme shock and vibration  
• Power management supported  
• NCQ command set  
• TRIM support  
• RAID support  
• SMART support

You can stack multiple PiDrives for a RAID setup. Each PiDrive will use one of the on-board Pi USB ports.

The PiDrive is Open Source. After successful completion of the campaign, all PiDrive related design files will be available to download.