I currently have two Retropie setups: one on a Raspberry Pi 3b and the other on a Raspberry Pi 4b. I did this to work through some issues I was having getting the OS updated from the Raspbian Stretch to Buster. Now that I have two working units, I brought one to the bavastudio to try and see how it looks attached to a 27″ CRT TV. Using a handy HDMI to RCA convertor I can take the signal from the Retropie and convert it to an AV signal that plugs right into an old school CRT TV’s RCA inputs. So, that’s easy enough.
After that, I needed to adjust the overscanning option on the Retropie to make sure it scales appropriately to the TV. To do this you take the SD card out of the Retropie and plug it into your computer and edit the config.txt file on that boot disk. The existing settings for overscanning were the following for me:
# uncomment this if your display has a black border of unused pixels visible
# and your display can output without overscan
#disable_overscan=1
# uncomment the following to adjust overscan. Use positive numbers if console
# goes off screen, and negative if there is too much border
overscan_left=16
overscan_right=16
overscan_top=32
overscan_bottom=64
I uncommented the disable_overscan option and set it to 0 and then commented out the rest:
# uncomment this if your display has a black border of unused pixels visible
# and your display can output without overscan
disable_overscan=0
# uncomment the following to adjust overscan. Use positive numbers if console
# goes off screen, and negative if there is too much border
#overscan_left=16
#overscan_right=16
#overscan_top=32
#overscan_bottom=64
I also tried to change some settings in the Retroarch config via the Retropie interface, but I’m not certain those changes made a difference. The above does get me consistently 4:3 Atari games on a 27″ TV with very little black space around the margins. It maps almost 1:1 against the actual Atari 2600 and 5200 consoles I have running on that TV—so I have a control to test with.
Next step will be trying this out on the Retropie 4b, but I do like that at least one of the Retropies is using a CRT rather than a 4K monitor—the latter just seems wrong for all kinds of reasons.
Any reason you’re not using the built in composite out from the Pis?
Hi Ryan,
I did try it on the Retropie 3b a while back and it wasn’t working for me, so I abandoned that approach (along with bluetooth wireless controllers). That said, it would be easier, so I need to return to that. I have a mini to composite around somewhere, so I will give that a go again on the 3b and test it on the 4B. The wireless controllers would be the real coup, so thanks for giving me the nudge.
As an update here, I did try the composite out on both the 3b and 4b Pies with no luck. The 3.5 mm mini jack to RCA I have must not be working correctly—which I am seeing is a common issue. I ordered a new one from Adafruit based on some recommendations in the forums, this will help confirm if the cable was the issue (I am thinking it might be).
Given what a PITA over scanning is proving on my Retropies, I’m hoping the jack out works and saves me from trying to play around with the overscanning settings in the config.txt file. I tried the same settings I listed above on my Raspberry Pi 4b, and nothing I did could get rid of 1.5″ black margins on the left and right of screen.