No Signal After Rebooting PI4B

helloThere

Current Set-up:
PI 4B 8GB
5.1 V 2.5A PSU
32 GB SD Card
128 GB Flash Drive

I was following this guide [1] and ran sudo rpi-update, then rebooted. When the PI 4B was booting, I noticed that there were no raspberries. The boot up text followed and they all came back fine. Then the screen just said no-signal and went black. But I tried to SSH into the PI and that seems to work.

I'm using the mini hdmi port right beside the USB-C power cable and I tried plugging it in and out between the 2 mini hdmi. What should I try to do?

[1]

mitu

rpi-update is not meant to be run as a regular update - it's a beta testing utility and shouldn't be used unless you want to latest kernel/firmware. Don't follow outdated video 'tutorials'.
Are you booting from the USB or the SD card ? You've not provided the full info asked in https://retropie.org.uk/forum/topic/3/read-this-first.

helloThere

@mitu sorry, that was a bit unclear, I'm still booting from an sd card. I haven't changed the settings yet.

I'll probably reflash the SD Card. Is there a better guide you'd reccomend for switching from SD Card to USB boot?

mitu

@hellothere said in No Signal After Rebooting PI4B:

I'll probably reflash the SD Card. Is there a better guide you'd reccomend for switching from SD Card to USB boot?

Just flash the latest RetroPie image to the USB drive and try to boot from it.

helloThere

@mitu okay, I'll do that in a bit. It just boots from usb automatically, if a usb device with updated software is detected? I thought I had to use an SD Card with retropie to update the EEPROM on the PI4 Board.

mitu

@hellothere said in No Signal After Rebooting PI4B:

I thought I had to use an SD Card with retropie to update the EEPROM on the PI4 Board.

Yes, you have, but since you already did that with your 1st SD card installation, your EEPROM should be already updated.

helloThere

@mitu I didn't get to that step yet, I was trying to update all the firmware on the PI (I thought that was necessary to update EEPROM), but before I could update EEPROM the monitor wasn't displaying output from the PI anymore.

I tried a fresh install of retropie onto an SD Card and that doesn't seem to work either. There is a quick screech in the audio and still nothing. I can't seem to find it on my network either, so I can't SSH in.

Maybe I can try different boards or a different SD card?

mitu

Do you get the bootloader diagnostic screen - https://www.raspberrypi.org/documentation/hardware/raspberrypi/boot_diagnostics.md ?
Run the EEPROM bootloader flash image - you can install it through the Raspberry Pi imager (see here) and choose what's the boot order (USB/SD-Card/etc.). Then try again to boot the USB flash with the RetroPie image.

helloThere

@mitu No, the monitor still says no signal and then just a black screen. I'll try that, too, thanks.

Just worried that I might have fried my board/card with sudo rpi-update, though I'm not sure if that's possible or not.

helloThere

@mitu I tried using an old sd card that worked before and the monitor still reads as no signal. I tried to SSH into it and terminal said "ssh: connect to host 10.1.10.182 port 22: Connection refused", so I must have disabled it before, but at least the SD Card seems to work. SSH seems to work, so I think the error's probably just with HDMI Output.

I'll get another board to see if there's something wrong with my current board. Is there a log file I can check to see if there's something wrong with the HDMI output?

mitu

@hellothere said in No Signal After Rebooting PI4B:

I'll get another board to see if there's something wrong with my current board. Is there a log file I can check to see if there's something wrong with the HDMI output?

Use tvservice -s to check if the display has been initialised and has a resolution, tvservice -m CEA or tvservice -m DMT to query the display for supported video modes.

helloThere

@mitu When I ran those tvservice commands, the monitor wasn't detected by the command line interface until I changed some lines in config.txt. But when I boot the monitor, it still says no signal, and the same result when I tried a different monitor. I also tried uncommenting hdmi_safe_mode.

pi@retropie:~ $ tvservice -s
state 0x6 [DVI CUSTOM RGB full 4:3], 640x480 @ 60.00Hz, progressive
pi@retropie:~ $ tvservice -m CEA
Group CEA has 4 modes:
           mode 4: 1280x720 @ 60Hz 16:9, clock:74MHz progressive 
           mode 16: 1920x1080 @ 60Hz 16:9, clock:148MHz progressive 
           mode 95: 3840x2160 @ 30Hz 16:9, clock:297MHz progressive 
           mode 97: 3840x2160 @ 60Hz 16:9, clock:594MHz progressive 
pi@retropie:~ $ tvservice -m DMT
Group DMT has 1 modes:
  (prefer) mode 4: 640x480 @ 60Hz 4:3, clock:25MHz progressive 
pi@retropie:~ $

This is how my config.txt looks right now. Is there anything something else I can do with config.txt or another way to try and get the hdmi output to work?

mitu

Not sure if the output was taken before or after you modified the config.txt, but the current resolution shows a (DMT) 640x480 resolution is used, while config.txt sets a (CEA) 720p video mode.
What kind of TV/monitor do you have ? tvservice shows some TV (CEA) video modes, but only 720p, 1080p and 4k(@30/@60) are shown, nothing in between - kind of unusual.

If using hdmi_safe doesn't output anything on your screen, then I'd try a different HDMI cable.

helloThere

@mitu My monitor's a 1766x720 if memory serves me right. It's an odd size, but by modifying the overscan a little bit, the output used to work just fine. I also tried a 1080x720 monitor.

If using hdmi_safe doesn't output anything on your screen, then I'd try a different HDMI cable.

I'll work on getting a new HDMI Cable, but currently I only have one.

I used a fresh PI4B Board, but kept everything else the same (SD Card, image, monitor), and the HDMI output worked for that. Is it possible I broke something on the old PI4B Board when I used rpi-update?

mitu

@hellothere said in No Signal After Rebooting PI4B:

Is it possible I broke something on the old PI4B Board when I used rpi-update?

Highly unlikely.

helloThere

@mitu I was overcomplicating the problem. Apparently I just needed to push the HDMI cable a little harder into the port. 🤣

The more you know. That probably should have been the first thing I tried, but thanks for the help!