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#1
ESP32 / Re: ESP32-P4-PC: USB-JTAG inst...
Last post by Rochus - October 19, 2026, 04:44:18 PMAs noted, Rev. C. I bought them on 19.02.2026, order W-RK180226. What other information do you need?
#2
New Products release / BB-LVL-SHIFT and UEXT-LVL-SHIF...
Last post by olimex - October 19, 2026, 03:27:42 PMTwo new Open Source Hardware boards in stock BB-LVL-SHIFT and UEXT-LVL-SHIFT allow 3.3V targets to tlk to 1.65V-5.5V sensors and targets https://olimex.wordpress.com/2026/10/19/two-new-open-source-hardware-level-shifters-bb-lvl-shift-and-uext-lvl-shift/ #oshw #embedded #esp32 #stm32 #arduino #raspberryrpi #maker #olimex
#3
Neo6502 / Re: Problems Getting Started
Last post by LubOlimex - October 19, 2026, 09:04:22 AMDo you use the left side connector initially? Only switch to the connector at the back after successfully downloading the firmware.
#4
ESP32 / Re: ESP32-P4-PC: USB-JTAG inst...
Last post by LubOlimex - October 19, 2026, 08:59:41 AMWhat is the hardware revision of the board that you use?
#5
Neo6502 / Re: Problems Getting Started
Last post by AFM - October 18, 2026, 06:09:04 PMI also have problem to getting started. Just got a Neo6502kbd. Manual says I need to press the bootloader, turn on then release the bootloader. There is a red light at the hdmi which lights up, then nothing happens. No picture no reaction. Then I have to re-plug the type-c to be able to do this again. Charger is 20W, it charges my phone, also hdmi + monitor works with my laptop. I use the back type-c which is the power.
What do I do wrong?
Thank you.
What do I do wrong?
Thank you.
#6
A64 / Re: Use USB OTG in host mode
Last post by winfried - October 18, 2026, 12:24:36 AMThanks for the solution.
Since my A64 olinuxino REV.E is a a64-olinuxino-2Ge8G not a a64-olonuxino-1Ge8GW, I changed the script:
Exchanged all "1Ge8GW" with "2Ge8G".
It worked fine as described, after reboot reconnect the mouse it lights and get listed with lsusb.
Will do some further checks for now and report if stable and seeing forward to the kernel fix.
Since my A64 olinuxino REV.E is a a64-olinuxino-2Ge8G not a a64-olonuxino-1Ge8GW, I changed the script:
Exchanged all "1Ge8GW" with "2Ge8G".
It worked fine as described, after reboot reconnect the mouse it lights and get listed with lsusb.
Will do some further checks for now and report if stable and seeing forward to the kernel fix.
#7
ESP32 / ESP32-P4-PC: USB-JTAG instabil...
Last post by Rochus - October 17, 2026, 12:22:39 AMWhile tying to migrate the Oberon System 3 to the P4-PC board I have hit the following road blocks (not sure whether this is the right place for this or it was already reported elsewhere):
Rev.C, behaviour reproduced on two separate boards
Not using any of your software or drivers
# 1. USB Serial/JTAG interface drops and re-enumerates continuously
Only started after several flashes and tests
/dev/ttyACM* node then appears and disappears every few seconds for some time with stable phases (~10 minutes) in between
# 2. LT8912B I2C interface strange behaviour when HDMI is connected
The LT8912B is on GPIO7/SDA + GPIO8/SCL
Once a monitor is attached, the LT8912B cannot be (re)configured
If the monitor is attached/detached after a working init, the LT
often loses its HDMI transmitter state and the display stays blue until the LT is re-initialized
Rev.C, behaviour reproduced on two separate boards
Not using any of your software or drivers
# 1. USB Serial/JTAG interface drops and re-enumerates continuously
Only started after several flashes and tests
/dev/ttyACM* node then appears and disappears every few seconds for some time with stable phases (~10 minutes) in between
# 2. LT8912B I2C interface strange behaviour when HDMI is connected
The LT8912B is on GPIO7/SDA + GPIO8/SCL
Once a monitor is attached, the LT8912B cannot be (re)configured
If the monitor is attached/detached after a working init, the LT
often loses its HDMI transmitter state and the display stays blue until the LT is re-initialized
#8
Neo6502 / Re: Prophet server for the Neo...
Last post by Ralf - October 16, 2026, 07:18:57 PMDude!
Your Trinity Firmware is the hottest thing for the Neo6502 since the original Prophet-Server!
Two things I noticed:
- the Olimex UART WiFi Card seems not to be supported. Fair enough, you offer a viable alternative. However, I guess you might want to state that more clearly somewhere. First boot of Trinity with the UART Card inserted resulted in a myriad of error messages and lots of unwanted files suddenly appearing on my USB drive.
- how is the state of the keymap support? Can I change to a German keymap already?
I must confess, I was skeptical at first, but then I found that NeoBASIC is still provided, and Wolfenstein 3d is a marvel in itself!
Absolutely love the name, by the way: Trinity! So fitting for the whole project, very nice.
Great work!
Cheers
Your Trinity Firmware is the hottest thing for the Neo6502 since the original Prophet-Server!
Two things I noticed:
- the Olimex UART WiFi Card seems not to be supported. Fair enough, you offer a viable alternative. However, I guess you might want to state that more clearly somewhere. First boot of Trinity with the UART Card inserted resulted in a myriad of error messages and lots of unwanted files suddenly appearing on my USB drive.
- how is the state of the keymap support? Can I change to a German keymap already?
I must confess, I was skeptical at first, but then I found that NeoBASIC is still provided, and Wolfenstein 3d is a marvel in itself!
Absolutely love the name, by the way: Trinity! So fitting for the whole project, very nice.
Great work!
Cheers
#9
A20 / Re: Wich board to correctly mo...
Last post by oly - October 16, 2026, 04:25:07 PMI replace the non SPI board with the SPI embendded one.
I burnt again the OlinuXino image on the SD card.
I pluged the SD card in the new board (with the initial HDD connected) and powered on.
The prompt displays the hostname set during the previous installation ...
Seems that OS is loaded from HHD.
What should I do in order to properly reset the all so that I can boot from the OS on the SD card then execute the tool olinuxino-sd-to-sata from it toward the HDD ?
Noted that during the first try on the previous board, the olinuxino-sd-to-sata tool transfers OS to the HDD then displayed an error regarding the absence of SPI where to copy the bootloader.
I burnt again the OlinuXino image on the SD card.
I pluged the SD card in the new board (with the initial HDD connected) and powered on.
The prompt displays the hostname set during the previous installation ...
Seems that OS is loaded from HHD.
What should I do in order to properly reset the all so that I can boot from the OS on the SD card then execute the tool olinuxino-sd-to-sata from it toward the HDD ?
Noted that during the first try on the previous board, the olinuxino-sd-to-sata tool transfers OS to the HDD then displayed an error regarding the absence of SPI where to copy the bootloader.
#10
A64 / Re: Use USB OTG in host mode
Last post by LubOlimex - October 16, 2026, 12:01:36 PMTested solution: A64-OLinuXino-1Ge4GW USB OTG with OLIMAGE
We reproduced the problem on A64-OLinuXino-1Ge4GW with kernel 5.10.180-olimex and found the cause.
It is possible to restore safe dual-role operation without rebuilding the complete image. We tested both USB-device mode and USB-host mode.
What is wrong
USB0 PHY0 is shared by MUSB, EHCI0 and OHCI0. The current device tree assigns PHY0 to all three controllers. During boot, EHCI0/OHCI0 requests host mode for PHY0. The sun4i PHY driver then stops following the USB0 ID pin, so normal OTG role switching fails.
The device-tree correction is:
Installation
Download install-a64-olinuxino-usb0-dual-role.sh. Log in as root and run:
If the script reports that the DTB was installed and the FIT image was rebuilt, disconnect everything from the micro-USB socket and reboot:
The script verifies the board, creates backups, modifies and checks a temporary DTB, installs it, and rebuilds /boot/kernel.itb.
It also generates the complete readable DTS here:
Generating the full DTS from the installed DTB is safer than distributing one hard-coded DTS, since phandles and other definitions can change between OLIMAGE kernel packages.
Important limitation
For the moment, boot with the micro-USB socket empty. After Linux has started, insert the OTG adapter.
If the adapter is already inserted during boot, the kernel detects the host role but does not initially enable VBUS. Removing and reinserting the adapter fixes it. This remaining boot-time problem requires a small MUSB driver correction; it cannot be fixed completely by the DTS alone.
Test results
Quick check
With the OTG socket empty:
Expected result:
After Linux has booted, insert the OTG adapter and check:
The attached detailed guide contains the manual procedure and recovery commands.
Permanent OLIMAGE fix
The OLIMAGE kernel package should eventually include both corrections:
After that, users should receive the complete fix normally through apt update, apt dist-upgrade, u-boot-install and reboot.
Until the fix is included in OLIMAGE, a future kernel package upgrade can replace the manually corrected DTB, in which case the workaround must be applied again.
We reproduced the problem on A64-OLinuXino-1Ge4GW with kernel 5.10.180-olimex and found the cause.
It is possible to restore safe dual-role operation without rebuilding the complete image. We tested both USB-device mode and USB-host mode.
What is wrong
USB0 PHY0 is shared by MUSB, EHCI0 and OHCI0. The current device tree assigns PHY0 to all three controllers. During boot, EHCI0/OHCI0 requests host mode for PHY0. The sun4i PHY driver then stops following the USB0 ID pin, so normal OTG role switching fails.
The device-tree correction is:
- MUSB remains connected to PHY0 and remains in "otg" mode.
- The "phys" and "phy-names" properties are removed only from EHCI0 and OHCI0.
- The USB0 VBUS regulator is not forced permanently on.
Installation
Download install-a64-olinuxino-usb0-dual-role.sh. Log in as root and run:
Code Select
cd /root
wget https://ftp.olimex.com/TEMP/A64-OTG-fix/install-a64-olinuxino-usb0-dual-role.sh
chmod 700 /root/install-a64-olinuxino-usb0-dual-role.sh
/root/install-a64-olinuxino-usb0-dual-role.sh
If the script reports that the DTB was installed and the FIT image was rebuilt, disconnect everything from the micro-USB socket and reboot:
Code Select
reboot
The script verifies the board, creates backups, modifies and checks a temporary DTB, installs it, and rebuilds /boot/kernel.itb.
It also generates the complete readable DTS here:
Code Select
/root/sun50i-a64-olinuxino-1Ge4GW-usb0-dual-role.dts
Generating the full DTS from the installed DTB is safer than distributing one hard-coded DTS, since phandles and other definitions can change between OLIMAGE kernel packages.
Important limitation
For the moment, boot with the micro-USB socket empty. After Linux has started, insert the OTG adapter.
If the adapter is already inserted during boot, the kernel detects the host role but does not initially enable VBUS. Removing and reinserting the adapter fixes it. This remaining boot-time problem requires a small MUSB driver correction; it cannot be fixed completely by the DTS alone.
Test results
- Normal cable to a PC: USB peripheral mode worked, and the board did not drive VBUS.
- OTG adapter inserted after boot: host mode selected and VBUS enabled automatically.
- Low-speed USB mouse enumerated through OHCI0.
- High-speed SanDisk flash drive enumerated through EHCI0 as /dev/sda.
- Removing the OTG adapter disabled VBUS and returned USB0 to the idle role.
Quick check
With the OTG socket empty:
Code Select
cat /sys/class/extcon/extcon0/state
Expected result:
Code Select
USB=0
USB-HOST=0
After Linux has booted, insert the OTG adapter and check:
Code Select
cat /sys/class/extcon/extcon0/state
lsusb -t
dmesg | tail -n 30
The attached detailed guide contains the manual procedure and recovery commands.
Permanent OLIMAGE fix
The OLIMAGE kernel package should eventually include both corrections:
- Remove the EHCI0/OHCI0 PHY0 claims from the A64-OLinuXino device tree, leaving MUSB responsible for PHY0.
- Make the sunxi MUSB driver synchronize the existing USB-HOST extcon state when it starts, so booting with an OTG adapter already inserted also works.
After that, users should receive the complete fix normally through apt update, apt dist-upgrade, u-boot-install and reboot.
Until the fix is included in OLIMAGE, a future kernel package upgrade can replace the manually corrected DTB, in which case the workaround must be applied again.