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fbergama / pigfx

PiGFX is a bare metal kernel for the Raspberry Pi that implements a basic ANSI terminal emulator with the additional support of some primitive graphics functions.
MIT License
275 stars 60 forks source link

Composite output #69

Closed esalgado closed 2 years ago

esalgado commented 2 years ago

Hello!

is it possible to use the Composite output instead of the HDMI? I.E. to hook it up to an old TV

Thanks for this awesome project :)

chregu82 commented 2 years ago

Hi As far as I know this should work out of the box.

esalgado commented 2 years ago

Hi! Thanks for the reply, I have tried with a working Composite cable, tested with Raspbian. Does not work with PiGFX on Pi 4:

https://www.raspberrypi.com/documentation/computers/config_txt.html

On the Raspberry Pi 4, composite output is disabled by default, due to the way the internal clocks are interrelated and allocated. Because composite video requires a very specific clock, setting that clock to the required speed on the Pi 4 means that other clocks connected to it are detrimentally affected, which slightly slows down the entire system. Since composite video is a less commonly used function, we decided to disable it by default to prevent this system slowdown.

To enable composite output, use the enable_tvout=1 option. As described above, this will detrimentally affect performance to a small degree.

Thanks!

chregu82 commented 2 years ago

Have you tried putting a config.txt onto the SD card with enable_tvout=1 ?

esalgado commented 2 years ago

OMG... yes it works!! I did not know I could also use config.txt with this...

Thanks a lot for your support :)