Changes between Version 6 and Version 7 of m2


Ignore:
Timestamp:
09/16/2021 10:04:39 PM (3 years ago)
Author:
Tim Harvey
Comment:

add additional information from M.2 specification

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  • m2

    v6 v7  
    1 = M.2 Form Factor =
     1[[PageOutline]]
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    3 The M.2 Form Factor, previously known as NGFF or Next Generation Form Factor is another form factor other than Mini-PCIe.
     3= M.2 Form Factor
     4The M.2 Form Factor, previously known as NGFF or Next Generation Form Factor is another form factor other than Mini-PCIe.
    45
    5 Gateworks uses Mini-PCIe connectors on most of their single board computers.
     6Gateworks uses [wiki:minipciexpressmodules Mini-PCIe] connectors on most of their single board computers.
    67
    7 There are many keying interfaces, with the most popular being B & M. Read more here: [https://en.wikipedia.org/wiki/M.2]
     8References:
     9 - https://en.wikipedia.org/wiki/M.2
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    9 Typically for a modem needing USB, this would utilize the B-Key which has PCIe ×2, SATA, USB 2.0 and 3.0, audio, UIM, HSIC, SSIC, I2C and SMBus. Even though these other signals are available, typically the modem will only require the USB signals.
     11== Keys and Sockets
     12M.2 connectors on the host are called 'sockets' and each socket has a unique mechanical key and modules are not interchangeable between sockets. The type of socket is based on the intended function of the card and can be thought of as a classification:
     13- Socket 1: connectivity socket for !WiFi, Bluetooth, NFC, or !WiGig
     14- Socket 2: WWAN/SSD/Other socket that supports various WWAN+GNSS solutions, various SSDs, and future
     15- Socket 3: SSD drive socket with SATA or up to four PCIe lanes
    1016
    11 The M key has PCIe ×4, SATA and SMBUS. Gateworks does not have any Mini-PCIe slots with 4x PCIe lanes, thus utilizing an adapter will not necessarily provide the full set of signals.
    1217
    13 If it is required to use a M.2 on a Gateworks SBC, Gateworks sells the [https://www.gateworks.com/products/mini-pcie-expansion-cards/gw1614x-mini-pcie-to-m2-adapter-card/ GW16140 Mini-PCIe to M.2 Adapter].
     18The physical Key prevents insertion of card connectors (male) to an incompatible socket (female) on the host. There are 12 key IDs on the module card and socket interface:
     19||= Key ID =||= Pin Location =||= Interfaces =||
     20|| A || 8-15 || 2x PCIe x1 / USB 2.0 / I2C / DP x4
     21|| B || 12-19 || PCIe x2 / SATA / USB 2.0 / USB 3.0 / HSIC / SSIC / Audio / UIM / I2C
     22|| C || 16-23 || Reserved for Future Use
     23|| D || 20-27 || Reserved for Future Use
     24|| E || 24-31 || 2x PCIe x1 / USB 2.0 / I2C / SDIO / UART / PCM
     25|| F || 28-35 || Future Memory Interface (FMI)
     26|| G || 39-46 || Not Used for M.2; for Custom / Non-Standard Apps
     27|| H || 43-50 || Reserved for Future Use
     28|| J || 47-54 || Reserved for Future Use
     29|| K || 51-58 || Reserved for Future Use
     30|| L || 55-62 || Reserved for Future Use
     31|| M || 59-66 || PCIe x4 / SATA
     32
     33
     34Typical Examples:
     35 * Cellular Model B-Key:
     36  - While the B-Key specifies pins for PCIe×2, SATA, USB2, USB3, audio, UIM, HSIC, SSIC, I2C and SMBus not all of these are necessary or supported on cards or host sockets.
     37  - Typically 3G/4G modems will only use the W_DISABLE#, RESET#, CARD_Power_OFF# GPIOs, USB2 and UIM signals.
     38  - Typically 5G modems will only use the W_DISABLE#, RESET#, CARD_Power_OFF# GPIOs, USB3 or PCIe, and UIM signals.
     39 * SSD M-Key:
     40  - Typically SSD's will use either PCIex4 or SATA for the data interface.
     41
     42Note that if a host socket of a specific key does not mean it implements all signaling defined by the specification and similarly if a add-in card of a specific key does not mean it implements all signalling defined by the specification. Look at the specification of the host socket and the add-in card carefully to determine needs and compatibility.
     43
     44== Notable GPIO's
     45There are a number of notable GPIO's that M.2 sockets and cards support
     46
     47Socket 1 GPIO specifications:
     48||= Name =||= card I/O =||= Voltage =||= Function =||= pulls =||
     49|| W_DISABLE1# || I || 3.3V || disable radio operation || active-low pull-up required on card when used ||
     50|| W_DISABLE2# || I || 3.3V || disable radio operation || active-low pull-up required on card when used ||
     51|| LED1# || O || 3.3V || card-specific LED
     52|| LED2# || O || 3.3V || card-specific LED
     53
     54
     55Socket 2 GPIO specifications:
     56||= Name =||= card I/O =||= Voltage =||= Function =||= pulls =||
     57|| W_DISABLE1# || I || 3.3V || disable radio operation || active-low pull-up required on card when used ||
     58|| W_DISABLE2# || I || 1.8V || disable radio operation || active-low pull-up required on card when used ||
     59|| FULL_CARD_POWER_OFF# || I || 1.8V (3.3V tollerant) || disable all services || active-low pull-down required on card ||
     60|| RESET# || I || 1.8V || reset all services || active-low ||
     61
    1462
    1563== GW16140 Mini-PCIe to M.2 Adapter
    16 This adapter allows you to plug in a M.2 modem to a Gateworks Mini-PCIe slot on the SBC.
    17  * https://www.gateworks.com/products/mini-pcie-expansion-cards/gw1614x-mini-pcie-to-m2-adapter-card/
     64If it is required to use a M.2 on a Gateworks SBC in a miniPCIe socket, Gateworks sells the [https://www.gateworks.com/products/mini-pcie-expansion-cards/gw1614x-mini-pcie-to-m2-adapter-card/ GW16140 Mini-PCIe to M.2 Adapter].
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