Frontend on raspberry pi 4

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yawlhoo
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Frontend on raspberry pi 4

Post by yawlhoo »

I am setting up a new frontend on a raspberry pi 4 with 4G ram. I am running raspian buster and mythtv-light.

Something is very wrong with sound sync, whereas the usual playback menu option allows one to adjust millisecond audio timing, I think in my case the sound leads the image several seconds.

Anyone encountered this in setting up a frontend?
MikeB2013
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Re: Frontend on raspberry pi 4

Post by MikeB2013 »

Not seen this audio problem.
How is the display connected, HDMI (using HDMI-0 the one nearest usb-c power connector) ?
What is the display configuration, use with mythtv-light of anything greater than 1080p does not work well for me (I am in UK, so it is 50Hz territory)?
You can get all of the information by using tvservice commands in a terminal session (I use ssh into pi4).

To get supported video modes, the current setting may have "(prefer)" at the start of the line

Code: Select all

tvservice -m CEA  
or if running as a monitor :

Code: Select all

tvservice -m DMT 
audio modes:

Code: Select all

tvservice -a  
Edit:
To get current screen mode, "(prefer)" does not always show current setting in tvservice -m CEA

Code: Select all

tvservice -s
yawlhoo
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Re: Frontend on raspberry pi 4

Post by yawlhoo »

Maybe the source of the problem is that the display is NOT going at 1080p.

tvservice -s gives:

state 0xa [HDMI CUSTOM RGB lim 16:9], 3840x2160 @ 30.00Hz, progressive

and tvservice -m CEA yields:

Group CEA has 22 modes:
mode 1: 640x480 @ 60Hz 4:3, clock:25MHz progressive
mode 2: 720x480 @ 60Hz 4:3, clock:27MHz progressive
mode 3: 720x480 @ 60Hz 16:9, clock:27MHz progressive
mode 4: 1280x720 @ 60Hz 16:9, clock:74MHz progressive
mode 5: 1920x1080 @ 60Hz 16:9, clock:74MHz interlaced
mode 7: 720x480 @ 60Hz 16:9, clock:27MHz x2 interlaced
mode 16: 1920x1080 @ 60Hz 16:9, clock:148MHz progressive
mode 17: 720x576 @ 50Hz 4:3, clock:27MHz progressive
mode 18: 720x576 @ 50Hz 16:9, clock:27MHz progressive
mode 19: 1280x720 @ 50Hz 16:9, clock:74MHz progressive
mode 20: 1920x1080 @ 50Hz 16:9, clock:74MHz interlaced
mode 22: 720x576 @ 50Hz 16:9, clock:27MHz x2 interlaced
mode 31: 1920x1080 @ 50Hz 16:9, clock:148MHz progressive
mode 32: 1920x1080 @ 24Hz 16:9, clock:74MHz progressive
mode 33: 1920x1080 @ 25Hz 16:9, clock:74MHz progressive
mode 34: 1920x1080 @ 30Hz 16:9, clock:74MHz progressive
mode 93: 3840x2160 @ 24Hz 16:9, clock:297MHz progressive
mode 94: 3840x2160 @ 25Hz 16:9, clock:297MHz progressive
(prefer) mode 95: 3840x2160 @ 30Hz 16:9, clock:297MHz progressive
mode 98: 4096x2160 @ 24Hz unknown AR, clock:297MHz progressive
mode 99: 4096x2160 @ 25Hz unknown AR, clock:297MHz progressive
mode 100: 4096x2160 @ 30Hz unknown AR, clock:297MHz progressive

It's not immediately clear to me how to force a different mode, but I will try to figure it out. Thanks for your feedback.
MikeB2013
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Re: Frontend on raspberry pi 4

Post by MikeB2013 »

If you are running at default (vc4-fkms-v3d) on Pi4, from Application menu>Preferences>Screen Configuration>Configure>Screens>HDMI-1 you can then set Resolution and Frequency.
yawlhoo
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Re: Frontend on raspberry pi 4

Post by yawlhoo »

It doesn't seem that many attempts at configuration "take." For example, one doc says to modify /boot/config.txt with:

hdmi_force_hotplug=1
hdmi_group=1
hdmi_mode=16

but doing such only results in a change in "preferred":

tvservice -m CEA
Group CEA has 22 modes:
mode 1: 640x480 @ 60Hz 4:3, clock:25MHz progressive
mode 2: 720x480 @ 60Hz 4:3, clock:27MHz progressive
mode 3: 720x480 @ 60Hz 16:9, clock:27MHz progressive
mode 4: 1280x720 @ 60Hz 16:9, clock:74MHz progressive
mode 5: 1920x1080 @ 60Hz 16:9, clock:74MHz interlaced
mode 7: 720x480 @ 60Hz 16:9, clock:27MHz x2 interlaced
(prefer) mode 16: 1920x1080 @ 60Hz 16:9, clock:148MHz progressive
mode 17: 720x576 @ 50Hz 4:3, clock:27MHz progressive
mode 18: 720x576 @ 50Hz 16:9, clock:27MHz progressive
mode 19: 1280x720 @ 50Hz 16:9, clock:74MHz progressive
mode 20: 1920x1080 @ 50Hz 16:9, clock:74MHz interlaced
mode 22: 720x576 @ 50Hz 16:9, clock:27MHz x2 interlaced
mode 31: 1920x1080 @ 50Hz 16:9, clock:148MHz progressive
mode 32: 1920x1080 @ 24Hz 16:9, clock:74MHz progressive
mode 33: 1920x1080 @ 25Hz 16:9, clock:74MHz progressive
mode 34: 1920x1080 @ 30Hz 16:9, clock:74MHz progressive
mode 93: 3840x2160 @ 24Hz 16:9, clock:297MHz progressive
mode 94: 3840x2160 @ 25Hz 16:9, clock:297MHz progressive
(native) mode 95: 3840x2160 @ 30Hz 16:9, clock:297MHz progressive
mode 98: 4096x2160 @ 24Hz unknown AR, clock:297MHz progressive
mode 99: 4096x2160 @ 25Hz unknown AR, clock:297MHz progressive
mode 100: 4096x2160 @ 30Hz unknown AR, clock:297MHz progressive

while everything stubbornly stays the same:

tvservice -s
state 0xa [HDMI CUSTOM RGB lim 16:9], 3840x2160 @ 30.00Hz, progressive

Trying the suggested menu item, I assume that one is supposed to enable the GL driver; but then it is found there is no 60Hz in the frequency list; maybe because of this, setting the "prefer" resolution does not take.
yawlhoo
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Re: Frontend on raspberry pi 4

Post by yawlhoo »

Whoops! I don't understand this, but somehow in repeatedly changing different settings, suddenly the lower resolution configuration took. Now I have:

$ tvservice -s
state 0xa [HDMI CEA (16) RGB lim 16:9], 1920x1080 @ 60.00Hz, progressive

and at this setting there is no audio delay problem.
yawlhoo
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Re: Frontend on raspberry pi 4

Post by yawlhoo »

Before I bought this Raspberry Pi 4, my frontend was a NUC: which has an IR detector, but no CEC. With the Pi, CEC, no IR.

So I bought a Flirc. Given the glowing statements about this gadget, I thought my worries were over.

Indeed, running thru up-left-down... initial button configuration lets the remote control basic functioning of Mythtv.

But what about all the other useful keys, Menu, FFWD, Bookmark,... etc.?

Is there any simple way to get the remote fully functioning with Mythtv?
yawlhoo
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Re: Frontend on raspberry pi 4

Post by yawlhoo »

I now have a Logitech 665 remote which I bought to help get the Flirc+MythTV set up.

Given the hype about Logitech Harmony remotes and the Flirc, I am surprised at how little info there is on getting things set up. The Flirc website seems practically useless. The Logitech Harmony site is predictable for mass software, the Flirc is almost beneath Logitech's interest, while MythTV might as well not exist as far as it is concerned.

It appears that adding a Flirc device with the MyHarmony setup works if the model is chosen as "Kodi." What about MythTV? Kodi != MythtTV.

I'll continue working on this, gritting my teeth as I am forced to use Windows, but I am not hopeful of getting anywhere given the almost total lack of information out there.
yawlhoo
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Posts: 120
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Re: Frontend on raspberry pi 4

Post by yawlhoo »

After struggling with this for a while, I have decided to ditch the Raspberry Pi 4 and the Flirc, and go back to the NUC as my frontend.

I am able to set up the Logitech Harmony remote using a MythTV wiki page:

https://www.mythtv.org/wiki/MyHarmony

and find that it works quite well.
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