sd card News - CNX Software - Embedded Systems News

October 20, 2023October 19, 2023 by Jean-Luc Aufranc (CNXSoft) - 4 Comments

microSD Express memory cards to support up to 2GB/s data transfers

SD Association (SDA) has announced the new SD 9.1 specification that doubles the speed of microSD Express memory card speed up to 2GB/s, defines four new SD Express Speed Classes to ensure guaranteed minimum sequential performance levels, and adds support for multi-stream access and related power and thermal management to assure the guaranteed performance. We first covered the microSD Express cards in 2019 as they were added to the SD 7.0 specification with promises of SSD performance through a PCIe 3.0 interface delivering up to 985MB/s. Over four years have passed since then, and I have yet to write about devices supporting the new standard, but the SD Association is not giving up with the introduction of the SD 9.1 specification that doubles the speed of the microSD Express cards, and full-size SD Express card can even reach close to 4GB/s. More specifically, the maximum speed achievable on microSD Express […]

May 20, 2020May 20, 2020 by Jean-Luc Aufranc (CNXSoft) - 17 Comments

SD 8.0 Specification Promises Dual-lane PCIe 4.0 SD Express Cards with up to 4GB/s Transfer Rate

SD 8.0 specification SD Express up to 4GB/s

The SD Association seems to be releasing new specifications faster than the industry and consumers can pick up. In June 2018, the SD 7.0 specification added SD Express cards with PCIe and NVMe interfaces for theoretical transfer rates up to 985 MB/s, followed by SD 7.1 specification in February 2019 adding SD Express to MicroSD card as well. The just-published SD 8.0 specification ups the ante further with SD Express now supporting dual-lane PCIe 4.0 with transfer rates up to 4GB/s. SD 8.0 is for full-sized SD Express cards that use the same NVMe upper-layer protocol, and remain backward compatible with earlier SD standards including UHS-III. The new higher bitrates will be used for data-intense wireless or wired communication, super-slow motion video, RAW continuous burst mode and 8K video capture and playback, 360-degree cameras/videos, gaming systems, multi-channel IoT devices, automotive devices etc… SD Express will be offered on SDHC, SDXC, […]

February 26, 2019February 26, 2019 by Jean-Luc Aufranc (CNXSoft) - 21 Comments

microSD Express Cards to Deliver SSD Performance

Last Summer the SD association released SD 7.0 specification with two key new features: SD Express adding PCIe and NVMe interfaces to the legacy SD card interface for transfer rates of up to 985MB/s, and SDUC (SD Ultra Capacity) card allowing capacities of up to 128 TB. This all looks great, but while the latter was available for both micro SD cards and full size SD cards, microSD cards could not benefit from the new high speed interfaces part of SD Express specification. SD 7.1 specification fixes that, as the SD association has now added microSD Express card which will also be able to reach up to 985MB/s (in theory) thanks to PCIe/NVMe interfaces, so we’ll be able to get sort of “removable SSDs” for smartphone and other devices that compatible with SD Express. As illustrated above microSD Express cards will be available in various capacities as microSDHC Express, microSDXC […]

October 7, 2018October 7, 2018 by Jean-Luc Aufranc (CNXSoft) - 38 Comments

The First Class A2 Micro SD Cards Launched for $30 and Up

Last year, the SD association introduced Class A2 application performance class for SD cards designed for optimal performance when running an OS or programs from the cards thanks to fast read and write random I/O, specifically 400O IOPS minimum for read operations, 2000 IOPS minimum for write operations. Since Class A2 was announced about 18 months ago, I simply assumed Class A2 SD cards were already available, but to my surprise I was wrong, as according to AnandTech, Sandisk Extreme micro SD cards are the first of the kind soon-to-be available commercially. Sandisk Extreme micro SD card specification: Capacity – 64GB, 128GB, 256GB, or 400GB Interface – UHS-I Sequential Speeds – Read: Up to 160 MB/s; Write: Up to 90MB/s (128GB to 400GB), up to 70MB/s (64GB) Random Speeds – Read: >= 4000 IOPS; Write: >=2000 IOPS SDA Labels – C10, U3, V30, A2 Temperature Range – -25 to 80°C […]

September 8, 2018September 8, 2018 by Jean-Luc Aufranc (CNXSoft) - 9 Comments

How to Make a Low Cost DIY SD Card Duplicator

If you have to duplicate many SD cards for example to boot Raspbian on multiple Raspberry Pi board, one option is buy one of those SD card duplicators, but the problem is that they are not really cheap, for example the Systor 1-to-7 cards model sells for $540. Bob Brown, a retired senior lecturer, is now teaching K-12 students how to get started with Raspberry Pi boards, and must prepare bootable SD cards for his class. In order to save time, a duplicator would have been nice, but the price is too high, so instead he went with a DIY solution. You’ll first need some hardware, including a powered USB hub with the number of cards you want to duplicate, and corresponding SD card reader, and a larger micro SD card to hold Raspbian and/or other operating systems (optional, only for Raspberry Pi based duplicator). Mr. Brown made a 10-port […]

July 10, 2018July 10, 2018 by Jean-Luc Aufranc (CNXSoft) - 3 Comments

SySTOR (Micro) SD Card Duplicators Can Handle Up to 200 SD Cards

So this week-end, I started to play with ROC-RK3328-CC (Renegade) board that I received from T-Chip / Firefly-Team and as always, I used Etcher to flash the firmware images to micro SD cards. Once flashing is complete, you’ll get a screen mentioning Etcher Pro, a standalone hardware solution allowing to duplicate the content of one micro SD card to 16 other cards. That’s very interesting if you need to duplicate many cards for a project, but the only problem is that the device is not available just yet. So I thought such equipment must already exist and indeed, a company called SySTOR offers such systems able to duplicate one (micro) SD card to up to 199 other (micro) SD cards. Some of the specifications & key features of the system: Processor – Multi-core processor System Memory – 256 MB DDR3 Capacity – Various models from 4 to 200 micro SD […]

June 28, 2018June 28, 2018 by Jean-Luc Aufranc (CNXSoft) - 3 Comments

SD Express Adds PCIe and NVMe Interfaces to SD Cards for up to 985 MB/s Transfer Rates

SD cards are known for the convenience, portability, and relatively cheap prices, but not so much for their performance which can be pretty poor especially for the cheaper and lower capacity models, and when fast random I/O is needed. The SD Association have been working on helping customer buy performant cards for their needs with – for instance – the app performance class introduced in SD 5.1 specification, which defines minimum random read and write speeds in Class A1 and Class A2 micro SD cards. However, the association has gone a step further with SD Express found in SD specification 7.0 that adds PCIe and NVMe interfaces to the legacy SD card interface. SD Express will enable theoretical data transfer rate up to 985 MB/s via PCIe 3.0, as well as advanced memory access mechanisms such as Bus Mastering, Multi Queue (without locking mechanism) and Host Memory Buffer thanks to […]

April 2, 2018April 3, 2018 by Jean-Luc Aufranc (CNXSoft) - No Comments

Linux 4.16 Release – Main Changes, Arm and MIPS Architectures

Linus Torvalds has just released Linux 4.16: So the take from final week of the 4.16 release looks a lot like rc7, in that about half of it is networking. If it wasn’t for that, it would all be very small and calm. We had a number of fixes and cleanups elsewhere, but none of it made me go “uhhuh, better let this soak for another week”. And davem didn’t think the networking was a reason to delay the release, so I’m not. End result: 4.16 is out, and the merge window for 4.17 is open and I’ll start doing pull requests tomorrow. Outside of networking, most of the last week was various arch fixlets (powerpc, arm, x86, arm64), some driver fixes (mainly scsi and rdma) and misc other noise (documentation, vm, perf). The appended shortlog gives an overview of the details (again, this is only the small stuff in […]