Frequently Asked Questions (FAQ) for AML-S805X-AC "La Frite"

What is it?

The Libre Computer AML-S805X-AC is a single-board computer (SBC) made by the Libre Computer Project, based on the Amlogic S-805X SoC.
It is nicknamed "La Frite".

Is there a Beginner's Guide for the Libre Computer AML-S805X-AC "La Frite" ?

Libre Computer has a Getting Started Guide written for the "Le Potato", much of it applies to the "La Frite".

How does it boot?

The Libre Computer AML-S805X-AC "La Frite" boots using u-boot, which is stored on the 16MB onboard SPI ROM. U-boot is the standard bootloader for ARM SBC's. U-boot can load the Linux kernel from a USB key, from a USB HDD or SSD, from an optional eMMC or from the network using a protocol called Preboot eXecution Environment or PXE (which assumes you have a DHCP/TFTP server configured to handle the requests from the "La Frite"). For development purposes the PXE method is the simplest and most practical, but for production use a USB key/HDD/SSD or eMMC are recommended, depending on the specific application.

Will it run Android?

Yes, the Libre Computer AML-S805X-AC "La Frite" has been demonstrated and benchmarked running Android Oreo 8.0 64-bit. So an Android Oreo image will most definitely be available before the "La Frite" begins shipping. Note you need the 1GB RAM version of the "La Frite" to run Android, and at the moment a Libre Computer eMMC module is also required.

Will it run OpenELEC (Open Embedded Linux Entertainment Center)?

Yes, there is already an image of OpenELEC compiled for the Libre Computer AML-S805X-AC "La Frite".

Will it run other Linux distributions?

Yes, the Libre Computer AML-S805X-AC "La Frite" will run any Linux distribution compiled for AArch64 (the ARM 64-bit architecture), among others Armbian, Ubuntu 18.04, Debian, Arch Linux Arm, etc.

What is the difference between the Libre Computer AML-S805X-AC "La Frite" and the Raspberry Pi 3 Model B/B+?

There are numerous differences broken down at three levels:

Hardware

  • Raspberry Pi 3 Model B+ is powered by the Broadcom BCM2837 SoC. This SoC is built on the 40nm process and has four ARM Cortex-A53 processors (with Crypto Extensions disabled) at 1.4GHz. The Broadcom proprietary GPU, which is also the boot device, is capable of OpenGL ES 2.0 and the video accelerator is capable of encoding and decoding H.264 at 1080P30. However, the GPU requires a closed-source firmware blob that only works in 32-bit mode. The Broadcom BCM2837 SoC features one USB 2.0 channel that is shared between all USB ports and Ethernet. It has onboard dual-band WiFi and Bluetooth. It features a non-UHS Micro-SD slot.
  • The "La Frite" is powered by the Amlogic S805X SoC. This is built on the 28nm process and has four ARM Cortex-A53 cores with Crypto Extensions at 1.2GHz. The ARM Mali-450MP GPU is capable of OpenGL ES 2.0 and the Amlogic Video Engine 10 video accelerator capable of encoding H.264 at 1080P30 and decoding H.265, H.264, and VP9 at 1080P60. It features two USB 2.0 channels with OTG functionality on one. Ethernet channel is dedicated with full speed and not part of the USB bus. It does not feature any onboard wireless radios. It features an eMMC connector and IR sensor. The PC board of the "La Frite" is smaller and shallower than the PC board of the Raspberry Pi 3 Model B/B+. Finally, idle, typical and maximum power consumption of the "La Frite" are all much smaller than for the Raspberry Pi 3 Model B/B+.

Software

  • Raspberry Pi's most popular distribution is Raspbian. The Debian Linux based distribution is compiled for the 32-bit ARMv6 instruction set to maintain backwards compatibility with the older Raspberry Pi models. There are a variety of other distributions that are compiled for 64-bit but they do not support video acceleration since Raspberry Pi's firmware does not support 64-bit mode. Due to the GPU design, it is not capable of supporting standard ARM64 kernels for unified software images.
  • The "La Frite" can run any Linux distribution compiled for 32-bit or 64-bit ARM architectures (including Raspbian). It features standardized upstream Linux kernel and u-boot and is fully compatible with future ARM standards like EBBR. It supports 3D and video acceleration through normal Linux kernel interfaces like DRM, KMS, GBM and V4L.

Community

  • Raspberry Pi has a large community of users exclusive to its ecosystem that provide support to each other.
  • The "La Frite" like the "Le Potato" and other Libre Computer SBC's, builds on upstream open-source projects (u-boot, the Linux kernel, Linux distributions such as Debian and Ubuntu, projects such as Kodi, etc) and communities that provide support for their respective projects.

Can I (add more salt to) overclock the "La Frite"?

The Libre Computer AML-S805X-AC "La Frite" can probably be mildly overclocked by tweaking the kernel. ;)
That said, if you need more speed, you'll also want more RAM, and then the "Le Potato" with 2GB RAM is what you really want.

What else do I need to use my "La Frite" when I get it in the mail?

If you pledged the "Small Meal with Fries" ($30) or the "Small Meal with Large Fries" ($35) during the Kickstarter campaign then you'll have (almost) everything you need: you'll probably want an Ethernet CAT5E cable to connect the "La Frite" to your Ethernet LAN, or a USB WiFi adapter to connect it to your home WiFi router.

At a minimum, this is what is required to test or use a "La Frite":

  1. A good-quality 5V 2.5A power supply with a micro USB connector (a new RPi Model 3 power supply should do fine).
  2. An Ethernet CAT5E (or CAT6) cable (or a supported USB WiFi adapter).
  3. Some form of storage for the operating system you intend to boot: either a Libre Computer eMMC module, or a USB key or USB HDD/SSD, or a properly setup DHCP/TFTP server if you intend to boot from the network.

Then, depending on what you intend to do with your "La Frite", you'll also need one or more of the following:

  1. An HDMI cable and an HDMI monitor or TV.
  2. A USB mouse and keyboard or a Bluetooth adapter and a Bluetooth mouse and keyboard (recommended).
  3. For kernel and u-boot hackers: a USB-to-serial adapter.

What is the "eMMC module" and why does it have to be a Libre Computer one?

The eMMC module is just a tiny PCB with an eMMC chip containing flash memory and a memory controller in the same package (you can think of it as a USB key without the USB interface). There is no industry standard pinout for EMMC modules so Libre Computer had to design their own. The "La Frite" has a connector for an optional Libre Computer eMMC module on the bottom of the PCB.

Can I emulate the "La Frite" on my desktop PC / notebook while I wait for the real thing to arrive?

Actually, provided you have a sufficiently recent machine with enough RAM, you can probably use QEMU to emulate the "La Frite" - sort of… ;) See this blog post for example.

Can you suggest a power supply for the "La Frite"?

As indicated before, any recent good-quality RPi Model 3 power supply rated 5V @ 2.5A should do fine. And no, that old smartphone charger rated 5V @ 1A you have in the back of the drawer is not a good choice. ;)
Again, you should shop for a good quality, regulated, 5V @ 2.5A power supply with a micro USB connector. These can be found at a number of online shops and are extremely affordable, but I suggest you stick to the shops that sell these power supplies specifically for SBC's such as the RPi Model 3.
Remember that by far the most common cause for instability, random reboots and lockups and other impossible-to-diagnose problems with SBC's is quite simply… a poor quality power supply.

Does the "La Frite" have GPIO pins?

Yes, the "La Frite" has a 40-pin GPIO header similar to the GPIO header on the Raspberry Pi A+, B+, Zero and Model 3 B/B+.

There are dozens of different Single Board Computers (SBC's) available, so what makes the "La Frite" unique?

There are quite a few things that make the "La Frite" different from most other SBC's on the market right now, let's list a few:

  • The price/performance ratio. At $10 for the 512MB RAM version or $15 for the 1GB RAM version (Kickstarter prices), the "La Frite" is by far the least expensive quad core ARM 64 bit SBC available on the market.
  • The size. At 64mm x 55mm and low height, the "La Frite" is quite small.
  • The availability of functional mainstream kernel and u-boot sources. This means you are not stuck with outdated versions of the kernel and the boot code. The importance of this cannot be emphasized enough: it means you can always build your own custom kernel and u-boot to suit your application.
  • The onboard 16MB SPI ROM with u-boot and the ability to boot using PXE. This can be a real plus for software development and specific applications.
  • The modern, powerful Amlogic Video Engine VPU with open-source support. Again, this cannot be emphasized enough. Thank to the excellent hard work by a team of dedicated developers (Maxime Jourdan, many others), the VPU on the Amlogic S805X is fully supported using open-source code and standard API's/libraries.
  • The 40-pin GPIO header. That is also a real plus for hackers/developers. Not all SBC's have a GPIO header available for experimenting purposes.

What are the recommended GCC compilation flags (CFLAGS) for natively compiling on the "La Frite"?

For compiling on the "La Frite", the following gcc flags are suggested:

CFLAGS="-march=armv8-a+crypto+crc -mtune=cortex-a53"

As a precautionary measure it is also suggested to stick to -O2 maximum optimization level during development.

Explanation:
"-mtune=cortex-a53" optimizes emitted code for the A53 cores.
"-march=armv8-a+crypto+crc" tells the assembler that the code generated can include instructions belonging to the ARMV8-A instruction set, plus CRC and Crypto extensions.

Please note that for compiling the Linux kernel itself, it is suggested not to add any CFLAGS, although the -march and -mtune flags above should be safe. And -O2 is the default set in the Linux kernel Makefile.

Reference: GCC docs

Would both u-boot and the Linux kernel fit in the onboard 16MB SPI ROM on the "La Frite"?

Yes indeed they would. The u-boot binary is under 1MB in size and the typical AArch64 Linux kernel is under 8MB. So both could fit in the 16MB SPI ROM with room to spare.