Hello everyone,
I currently have 4 Arduinos connected to my Rasp Pi4 with AP (3 MEGA2560 and 1 Pro Micro). Now I wanted to add another Arduino Micro (not a Sparkfun Pro Micro, just the offical Arduino Micro), but the Rasp Pi4 doesn't recognize it.
The micro is flashed correctly via AM and is also easily recognized on the PC.
What could be the reason? Please help.
Thanks a lot in advance
Marcus
Arduino Micro is not recognized by the Raspi4
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SimPassion
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Re: Arduino Micro is not recognized by the Raspi4
https://www.raspberrypi.com/products/ra ... 4-model-b/
Hi Marcus, are you using an USB Hub ? If yes, is it self-powered ?
Now, quick point from Google pointing to raspberrypi documentation on Github :
The Raspberry Pi 4 contains two USB 3.0 ports and two USB 2.0 ports which are connected to a VL805 USB controller. The USB 2.0 lines on all four ports are connected to a single USB 2.0 hub within the VL805: this limits the total available bandwidth for USB 1.1 and USB 2.0 devices to that of a single USB 2.0 port.
https://github.com/raspberrypi/document ... ry-pi.adoc
Known USB Issues
Interoperability with USB 3.0 hubs
There is an issue with USB 3.0 hubs in conjunction with the use of full or low speed devices, including most mice and keyboards. A bug in most USB 3.0 hub hardware means that the models prior to Raspberry Pi 4 cannot talk to full or low speed devices connected to a USB 3.0 hub.
USB 2.0 high speed devices, including USB 2.0 hubs, operate correctly when connected via a USB 3.0 hub.
Avoid connecting low or full speed devices into a USB 3.0 hub. As a workaround, plug a USB 2.0 hub into the downstream port of the USB 3.0 hub and connect the low speed device, or use a USB 2.0 hub between the Raspberry Pi and the USB 3.0 hub, then plug low speed devices into the USB 2.0 hub.
Single TT USB hubs
USB 2.0 and 3.0 hubs have a mechanism for talking to full or low speed devices connected to their downstream ports called a transaction translator (TT). This device buffers high speed requests from the host and transmits them at full or low speed to the downstream device. Two configurations of hub are allowed by the USB specification: Single TT (one TT for all ports) and Multi TT (one TT per port). Because of a hardware limitation, if too many full or low speed devices are plugged into a single TT hub, the devices may behave unreliably. It is recommended to use a Multi TT hub to interface with multiple full and low speed devices. As a workaround, spread full and low speed devices out between the Raspberry Pi’s own USB port and the single TT hub.
Hi Marcus, are you using an USB Hub ? If yes, is it self-powered ?
Now, quick point from Google pointing to raspberrypi documentation on Github :
The Raspberry Pi 4 contains two USB 3.0 ports and two USB 2.0 ports which are connected to a VL805 USB controller. The USB 2.0 lines on all four ports are connected to a single USB 2.0 hub within the VL805: this limits the total available bandwidth for USB 1.1 and USB 2.0 devices to that of a single USB 2.0 port.
https://github.com/raspberrypi/document ... ry-pi.adoc
Known USB Issues
Interoperability with USB 3.0 hubs
There is an issue with USB 3.0 hubs in conjunction with the use of full or low speed devices, including most mice and keyboards. A bug in most USB 3.0 hub hardware means that the models prior to Raspberry Pi 4 cannot talk to full or low speed devices connected to a USB 3.0 hub.
USB 2.0 high speed devices, including USB 2.0 hubs, operate correctly when connected via a USB 3.0 hub.
Avoid connecting low or full speed devices into a USB 3.0 hub. As a workaround, plug a USB 2.0 hub into the downstream port of the USB 3.0 hub and connect the low speed device, or use a USB 2.0 hub between the Raspberry Pi and the USB 3.0 hub, then plug low speed devices into the USB 2.0 hub.
Single TT USB hubs
USB 2.0 and 3.0 hubs have a mechanism for talking to full or low speed devices connected to their downstream ports called a transaction translator (TT). This device buffers high speed requests from the host and transmits them at full or low speed to the downstream device. Two configurations of hub are allowed by the USB specification: Single TT (one TT for all ports) and Multi TT (one TT per port). Because of a hardware limitation, if too many full or low speed devices are plugged into a single TT hub, the devices may behave unreliably. It is recommended to use a Multi TT hub to interface with multiple full and low speed devices. As a workaround, spread full and low speed devices out between the Raspberry Pi’s own USB port and the single TT hub.
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SimPassion
- Posts: 5340
- Joined: Thu Jul 27, 2017 12:22 am
Re: Arduino Micro is not recognized by the Raspi4
It appears the solution would be to connect all Arduino boards only through an USB 2.0 connection, so in this case the 5 x Arduino boards
Better to use a self powered USB 2.0 Hub connected to an USB 2.0 port on the Rasp Pi4 (one of the most two left black ports on the Rasp Pi4)
Better to use a self powered USB 2.0 Hub connected to an USB 2.0 port on the Rasp Pi4 (one of the most two left black ports on the Rasp Pi4)
Re: Arduino Micro is not recognized by the Raspi4
Hello,
Thanks to your tip I was able to solve the problem. I have now put all devices on a 2.0 port (self-powered) and left the 3.0 port empty. All devices are now working.
It might also be interesting to mention that even after the above change, the USB connection to the Arduino Micro was repeatedly interrupted when FS2020 was running. I was able to find the error: In addition to a few buttons and LEDs, an HD4470-based 2x16 character display is also connected to the micro. And every time the second line of the display is written with all 16 characters, the USB connection breaks. I'm now forced to use only the first 14 characters of the display, but that's fine for me.
Thank you
Marcus
Thanks to your tip I was able to solve the problem. I have now put all devices on a 2.0 port (self-powered) and left the 3.0 port empty. All devices are now working.
It might also be interesting to mention that even after the above change, the USB connection to the Arduino Micro was repeatedly interrupted when FS2020 was running. I was able to find the error: In addition to a few buttons and LEDs, an HD4470-based 2x16 character display is also connected to the micro. And every time the second line of the display is written with all 16 characters, the USB connection breaks. I'm now forced to use only the first 14 characters of the display, but that's fine for me.
Thank you
Marcus
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SimPassion
- Posts: 5340
- Joined: Thu Jul 27, 2017 12:22 am
Re: Arduino Micro is not recognized by the Raspi4
I guess this issue should be solved by introducing some small delay amount between line#1 end line#2 data send in your script, something like not more than a few tens of milliseconds max, just a matter to try ...Marcus wrote: ↑Sat Mar 11, 2023 4:28 pm Hello,
Thanks to your tip I was able to solve the problem. I have now put all devices on a 2.0 port (self-powered) and left the 3.0 port empty. All devices are now working.
It might also be interesting to mention that even after the above change, the USB connection to the Arduino Micro was repeatedly interrupted when FS2020 was running. I was able to find the error: In addition to a few buttons and LEDs, an HD4470-based 2x16 character display is also connected to the micro. And every time the second line of the display is written with all 16 characters, the USB connection breaks. I'm now forced to use only the first 14 characters of the display, but that's fine for me.
Thank you
Marcus
Re: Arduino Micro is not recognized by the Raspi4
I assumed that at first and added a delay of up to 500ms. But that didn't help either. Even if I only write the 2nd line, the problem occurs. But it only occurs on the 2nd line and only in combination with the Raspi. I tested the HW instrument on the PC beforehand and the problem did not occur there.
Re: Arduino Micro is not recognized by the Raspi4
Did you check if it is visible in the device list in the Pi OS?
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SimPassion
- Posts: 5340
- Joined: Thu Jul 27, 2017 12:22 am
Re: Arduino Micro is not recognized by the Raspi4
Could you please post your script to see if we can enhance it together ?Marcus wrote: ↑Sun Mar 12, 2023 1:43 pm I assumed that at first and added a delay of up to 500ms. But that didn't help either. Even if I only write the 2nd line, the problem occurs. But it only occurs on the 2nd line and only in combination with the Raspi. I tested the HW instrument on the PC beforehand and the problem did not occur there.