In 2023 the good approach is R5C

From the doc here :
https://wiki.friendlyelec.com/wiki/inde ... _package_2
The GPIOs are presently used for three UART. Who will use this ? You can disable UART and reuse the GPIO for your needs.
Note I have not tested this so I cannot guide you.

I am trying to build a kernel module. Following the procedure of the Wiki (8.7) here : https://wiki.friendlyelec.com/wiki/index.php/NanoPi_R5S#Install_the_kernel-header_package_2 I was able to build the module given as an example but for the last step : modprobe and insmode say that the exec format ...

Fortunately, there is now another solution. With a recent eFlasher, even if I had to mask the eMMC to start it from the SD card, it was able to recognize the eMMC and to flash a FriendlyElec OS on it. So the problem is now solved for me.

At last, a solution is here. With a recent eflasher, even if I had to mask the eMMC to start it from the card, it was able to find the eMMC and flashed a FriendlyElec OS on it. The problem is now solved.

UPDATE : This problem is solved, see the third message. Developers should be aware that if they develop a system which does not have the FriendlyElec boot loader, but use the Mainline U-Boot, it they load this system in eMMC and anything happens which prevents the system to boot, there is NO WAY AT...

I tried with an older version of RKDevTool (2.58). The result is the same. 14:00:44 896 Error:RKU_Write-->WriteFile failed,bRet=0,err=31,size=31,write=0 14:00:57 442 ERROR:RKU_ResetPipe-->DeviceIoControl failed,err=995 14:00:57 443 <LAYER 1-1-3> ERROR:TestDevice-->RKU_TestDeviceReady failed,RetCode(...

Without providing a serial console log collected via the debug UART, no one knows what's going on and no more comprehensive support can be provided. I don't think UART data is useful. There is no problem about the boot process, it is very well known : if a system with a non Friendly Elec is loaded ...

Unfortunately, I have been unable to reproduce what you say : even with the shortest time possible which allows booting on the SD card, the eMMC is not visible. I sent a message to the technical support but never got an answer. Excellent device, but total lack of technical support. This is regrettab...

I have a R5S used for development. I loaded in eMMC an image which failed. It has an uboot loader, and for this reason it is no longer possible to boot on a SD card without masking the eMMC. The only possible way to repair the device is to use the tool RKdev. Everything I tried failed. Connection is...

I think there is a connector for the clock battery. But I did not test.

The problem was that the cable on our system does not support GB. The os (Ubuntu 20) did not check this correctly and since adapters at the end of the connexion were both GB capable, the connection was set to GB, which could not work for us (it requires four pairs, and we have two). The solution was...

When connected to my Box (Orange Pro), and set to DHCP, ,the eth0 port does not get an IPv4 address. ifdown / if up shows DHCPDISCOVER but no DHCPOFFER. Set in the same way, eth1 and eth2 work fine (two DHCPDISCOVER and after the second DHCPOFFER etc. When eth0 is connected to a second R5S which has...

Which image are you using ? I have three R5S, they work fine. I am using eflasher images (Ubuntu or Debian) on microSD 32G cards