Olimex has designed several system-on-modules (SoM) over the years for on various processors such as Rockchip RK3188, TI AM3352, or Allwinner A20, and each time they focus on exposing as many pins as possible from the SoC. That’s nice for some application, but it also means SoM with different processor are not compatible, and you can’t simply design a single baseboard for all those SoMs.
Olimex then realized many customers wanted an upgrade path for the SoM without having to redesigned the baseboard, and most were using the same common interfaces, so a family of compatible SoMs was needed. While there are already many system-on-module standards available, the company decided to roll their own SoM form factor based on the 204-pin SO-DIMM edge connector.
The first SoM based on the standard will be A20-SOM204 powered by the popular Allwinner A20 processor. All SoM following this standard will expose the following interfaces through the edge connector:
- USB-OTG, 2x USB-HOST, HSIC, USB3
- PCIe
- 2x Fast/Gigabit Ethernet
- WiFi+BLE
- SATA, SD-CARD
- CAN
- IR
- CSI
- HDMI, VGA
- Audio In, Audio Out, SPDIF
- UEXT1 -> SPI1, I2C1, UART1
- UEXT2 -> SPI2, I2C2, UART2
There’s also a SOM204-EVB baseboard that should be compatible with all variants of those SoMs.
You’ll find some more information, including the schematics – about the current Allwinner A20 and EVB on the SOM204 page. The company expects to design SOM204 module based on Texas Instruments AM335x, Rockchip RK3399, and RK3288, meaning they’ll have a family of modules with the following options:
- Processor – Dual Core Cortex-A7 to Hexa Core Cortex-A72/A53
- System Memory – 1 to 4GB DDR3L
- Storage – 4 to 64GB eMMC
- Temperature Range – 0 to 70°C Commercial grade; -25 to +85°C Industrial grade
Long term supply will be guaranteed for the module, although not fixed amount of years has been given, and on the software side, Android and Linux will be supported, likely depending on the SoC used.
Pricing and availability information are unknown at this stage, but we do know they’ll keep on manufacturing the old models of system-on-module too.
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Jean-Luc started CNX Software in 2010 as a part-time endeavor, before quitting his job as a software engineering manager, and starting to write daily news, and reviews full time later in 2011.
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