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by jdb
Thu Sep 12, 2019 7:33 pm
Forum: Troubleshooting
Topic: Raspberry Pi 4 temperature
Replies: 564
Views: 182009

Re: Raspberry Pi 4 temperature

Feel free to disagree with me, but it would be nice to actually say what you're disagreeing on, and what you're calling "half-formed opinions". They're better than just blatant criticism without any ground. Back to frying eggs on a pi 4. I'm not disagreeing with you, because that would imply there ...
by jdb
Thu Sep 12, 2019 4:31 pm
Forum: General discussion
Topic: RPI 4 USB-C supply
Replies: 37
Views: 1856

Re: RPI 4 USB-C supply

The clue is this line: The circuitry required to manage the charging rate and voltage limits for lithium ion batteries is typically part of the device being charged (such as your cell phone or laptop), not the charger. With the charging control managed by the device that a charger brick is connected...
by jdb
Thu Sep 12, 2019 2:02 pm
Forum: Troubleshooting
Topic: VLI firmware v2.0 - powersaving features enabled
Replies: 102
Views: 13304

Re: VLI firmware v2.0 - powersaving features enabled

OK, so that confirms there's no issue with the firmware update - just that the utility is leaving the chip in an odd state that can cause a shutdown hang. I can replicate the hang, but only with USB3.0 devices attached. I tested with a mass storage device (filesystem not mounted) and a USB-HDMI adap...
by jdb
Thu Sep 12, 2019 6:46 am
Forum: Troubleshooting
Topic: Raspberry Pi 4 temperature
Replies: 564
Views: 182009

Re: Raspberry Pi 4 temperature

When you look at the sales of the 4B, you can clearly see there's a market for a pi desktop replacement , and for many, the 4B isn't that one yet. It would make sense to continue the trend of more power, more options, less heat, to satisfy that market. But if you ask me, I think the pi is popular b...
by jdb
Wed Sep 11, 2019 4:01 pm
Forum: Troubleshooting
Topic: VLI firmware v2.0 - powersaving features enabled
Replies: 102
Views: 13304

Re: VLI firmware v2.0 - powersaving features enabled

The use of the PCIe bounce buffers has been known to cause variable performance, especially when operating at near 100% utilisation of the PCIe link. Can you add total_mem=3072 to /boot/config.txt prior to retesting? This will limit the available ARM memory to the bottom 3G which should remove the b...
by jdb
Wed Sep 11, 2019 1:38 pm
Forum: General discussion
Topic: Raspberry Pi 4 Thread - general discussion
Replies: 895
Views: 104981

Re: Raspberry Pi 4 Thread - general discussion

This question also interests me. Does anyone know the answer to it? Another great product from the Raspberry Pi team. Can't wait to get my hands on one (when the 4GB ones are back in stock). I believe it has been fixed. Hi all, I have tested the I2C clock stretching feature of Raspberry Pi 4. unfor...
by jdb
Wed Sep 11, 2019 11:48 am
Forum: Troubleshooting
Topic: VLI firmware v2.0 - powersaving features enabled
Replies: 102
Views: 13304

Re: VLI firmware v2.0 - powersaving features enabled

The fact that you flashed the EEPROM twice (with the updated version) and fixed the issue suggests that something went wrong during the first flash.

Unfortunately both EEPROMs are now in a "good" state so there's not really any information that can be gotten out of them...
by jdb
Wed Sep 11, 2019 9:59 am
Forum: Troubleshooting
Topic: VLI firmware v2.0 - powersaving features enabled
Replies: 102
Views: 13304

Re: VLI firmware v2.0 - powersaving features enabled

Hesitant to make this a sticky (we have enough of them already) so - bump. I think a few more +1's for success and we put this in the announcements forum.
by jdb
Wed Sep 11, 2019 9:57 am
Forum: Advanced users
Topic: add electrolytic capacitor on power?
Replies: 23
Views: 4937

Re: add electrolytic capacitor on power?

- Don't necro old posts
- Don't flamebait other forum users.
by jdb
Wed Sep 11, 2019 9:40 am
Forum: General discussion
Topic: RPi4 pyusb and libusb1 detach kernel driver
Replies: 2
Views: 143

Re: RPi4 pyusb and libusb1 detach kernel driver

Can you post the code you are using?
by jdb
Wed Sep 11, 2019 7:59 am
Forum: General discussion
Topic: Super new to this and need help badly
Replies: 18
Views: 895

Re: Super new to this and need help badly

ProDigit wrote:
Wed Sep 11, 2019 7:34 am
If the green lan light is on, it should be working.
Especially if the orange light is flickering
Incorrect. Under stable link conditions you will see:
- Orange light solid on or solid off (speed indication)
- Green light on, but blinks when there is activity.
by jdb
Mon Sep 09, 2019 2:28 pm
Forum: Troubleshooting
Topic: VLI firmware v2.0 - powersaving features enabled
Replies: 102
Views: 13304

Re: VLI firmware v2.0 - powersaving features enabled

I can confirm that the VBus behaviour is identical across bootloader POWER_OFF_ON_HALT=0/1 and VLI firmware changes. One thing to note is that both of you are running the root on an SSD - if USB devices become inaccessible after flashing the firmware (the script rescans the bus) then a shutdown will...
by jdb
Mon Sep 09, 2019 9:05 am
Forum: Troubleshooting
Topic: VLI firmware v2.0 - powersaving features enabled
Replies: 102
Views: 13304

Re: VLI firmware v2.0 - powersaving features enabled

By removing devices do you mean the boot device or any attached? I'll measure the voltage in a bit, where is a good place to probe -ve ? The test is to remove USB devices while in the hung state and see if the Pi "wakes up". The SD card activity LED should still work and you should get the rainbow ...
by jdb
Mon Sep 09, 2019 8:46 am
Forum: Troubleshooting
Topic: VLI firmware v2.0 - powersaving features enabled
Replies: 102
Views: 13304

Re: VLI firmware v2.0 - powersaving features enabled

Weird. Injecting current into the D+/D- lines has been known to stop the PMIC from starting up as it causes leakage into the 3.3V supply. The only way that the firmware could be changing this behaviour is if Vbus isn't removed during device reset - worth investigating. Not the case in this instance...
by jdb
Sun Sep 08, 2019 5:29 pm
Forum: General discussion
Topic: Raspberry Pi 4 usb boot?
Replies: 411
Views: 89507

Re: Raspberry Pi 4 usb boot?

Then make a chainloader. USB boot is intentionally limited in scope to "find the first valid boot disk and boot from it".
by jdb
Sun Sep 08, 2019 3:46 pm
Forum: Troubleshooting
Topic: VLI firmware v2.0 - powersaving features enabled
Replies: 102
Views: 13304

Re: VLI firmware v2.0 - powersaving features enabled

"A PNY SSD" - what is it?

Is the drive enclosure USB3.0 to SATA? USB2.0 to SATA? Externally powered/bus-powered?
by jdb
Sun Sep 08, 2019 3:44 pm
Forum: General discussion
Topic: Raspberry Pi 4 usb boot?
Replies: 411
Views: 89507

Re: Raspberry Pi 4 usb boot?

The question is moot - in the existing implementation on Pi3B+, all connected USB devices are enumerated and probed to get a list of mass-storage devices. The first device that has a valid bootcode.bin is used to boot from. An analogue of this will be used on Pi 4, so as to not break USB disk images...
by jdb
Sat Sep 07, 2019 6:56 am
Forum: Troubleshooting
Topic: VLI firmware v2.0 - powersaving features enabled
Replies: 102
Views: 13304

Re: VLI firmware v2.0 - powersaving features enabled

Weird. Injecting current into the D+/D- lines has been known to stop the PMIC from starting up as it causes leakage into the 3.3V supply.
The only way that the firmware could be changing this behaviour is if Vbus isn't removed during device reset - worth investigating.
by jdb
Fri Sep 06, 2019 6:30 pm
Forum: Troubleshooting
Topic: VLI firmware v2.0 - powersaving features enabled
Replies: 102
Views: 13304

Re: VLI firmware v2.0 - powersaving features enabled

Are there any differences when rotating through the various ASPM power state options?

I.e. is the bandwidth significantly altered by doing

Code: Select all

# setpci -s 01:00.0 0xD4.B=0x40
# setpci -s 01:00.0 0xD4.B=0x41
# setpci -s 01:00.0 0xD4.B=0x43
in turn?
by jdb
Fri Sep 06, 2019 2:36 pm
Forum: Troubleshooting
Topic: Raspberry Pi 4 - new VLI firmware issues
Replies: 69
Views: 19995

Re: Raspberry Pi 4 - new VLI firmware issues

Locking this thread as there's a new version that needs testing -> https://www.raspberrypi.org/forums/view ... 8&t=250990
by jdb
Fri Sep 06, 2019 2:35 pm
Forum: Troubleshooting
Topic: VLI firmware v2.0 - powersaving features enabled
Replies: 102
Views: 13304

VLI firmware v2.0 - powersaving features enabled

We have received an updated USB controller firmware from VLI. This firmware enables PCIe APSM and should not have the device hang issues seen with the 0137a8. It should also resolve issues seen with poor performance when single USB2.0 devices were intermittently transferring data. Download the firmw...
by jdb
Thu Sep 05, 2019 12:58 pm
Forum: General discussion
Topic: Raspberry Pi computer looks down on Earth
Replies: 15
Views: 963

Re: Raspberry Pi computer looks down on Earth

Now, if we can crack the environmental impact of the launch as well... Assuming a kerosene/LOX or methane/LOX first-stage rocket, the 400-odd tons of fuel consumed in a launch is equivalent to what vehicles on the entire United States highway system use in 30 minutes. As the fuel is burned in pure ...
by jdb
Tue Sep 03, 2019 8:07 am
Forum: Troubleshooting
Topic: Raspberry Pi 4 temperature
Replies: 564
Views: 182009

Re: Raspberry Pi 4 temperature

"Soft Throttle" was implemented on 3B+ because the 1.2GHz operating point had a significant power saving compared to the 1.4GHz operating point - both frequency and core voltage could be reduced. The frequency reduction is only 15% in this case. On Pi 4, the first step down is 1GHz (33%) with no vol...
by jdb
Fri Aug 30, 2019 9:53 am
Forum: Beginners
Topic: 10 Beginner tips to get the most out of your pi
Replies: 3
Views: 266

Re: 10 Beginner tips to get the most out of your pi

It's not a question of agreement or typos. There are multiple factually incorrect parts to the post.
by jdb
Thu Aug 29, 2019 2:48 pm
Forum: Troubleshooting
Topic: Raspberry 4 OTG mode
Replies: 3
Views: 742

Re: Raspberry 4 OTG mode

https://learn.adafruit.com/turning-your-raspberry-pi-zero-into-a-usb-gadget/ethernet-gadget Works just as well on a Pi 4 as on a Zero. You will need to use a USB type A to C cable and the upstream port needs to be capable of high current (a default USB2.0 port will only supply 500mA, which is not en...

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