3.2" SPI LCD (working and ready for a build)

[VeteranGamer]

I can get those screens in wide viewing angle like the new mintyPi LCDs I got for this batch. There is a a few weeks wait time since they have to be made but I can usually get samples, let me know if you need my help acquiring some.

thanks....

that will help alot.....

i just blizts alibaba with enquiries, and am wating and going through replies.....

[YaYa]

Choosing between 3.2’’ clear wide angle or 3.5’’ crappy messy stuff... the choice is obvious for me.

[moosepr]

they design the screens to be used vertically with the chip down at the bottom. Its a common issue with the cheaper end of the screens, i had the same issue with TinyPi, although i could get the screen in its 'proper' orientation so its not too bad

https://twitter.com/Pi0CKET/status/846422958964924416

[moosepr]

So I got the old test rig out to test the overclock impact on screen speed. Used the overclock settings I found here
https://github.com/RetroPie/RetroPie-Se ... erclocking

So we've up adding this to the config

arm_freq=1000
gpu_freq=500
core_freq=500
sdram_freq=500
sdram_schmoo=0x02000020
over_voltage=2
sdram_over_voltage=2

And things broke

IMG_20171017_214827.jpg (2.21 MiB) Viewed 7328 times

Dropped the speed back down to 80000000 and the screen worked again, but the debug messages were flicking round 33fps still!

It's weird though, even when it's too fast for the screen to cope, it still doesn't get over 33fps

[YaYa]

Human eyes are working at 24FPS. Pal systems are using 25, NTSC is using 30FPS.
The original megadrive and snes were designed for those system. I’m not sure they were natively running more than 30...
So is it really an issue to have a flat 33 if it is stable and continuous ?

[VeteranGamer]

So I got the old test rig out to test the overclock impact on screen speed. Used the overclock settings I found here
https://github.com/RetroPie/RetroPie-Se ... erclocking

So we've up adding this to the config

arm_freq=1000
gpu_freq=500
core_freq=500
sdram_freq=500
sdram_schmoo=0x02000020
over_voltage=2
sdram_over_voltage=2

And things broke

IMG_20171017_214827.jpg

Dropped the speed back down to 80000000 and the screen worked again, but the debug messages were flicking round 33fps still!

It's weird though, even when it's too fast for the screen to cope, it still doesn't get over 33fps

i think 33fps could be the max these screens can push/handle.....

i also have a feeling (and its an ignorant feeling) that the bigger the screen the more you can throw at it (ie 2.4". 2.8" & 3.2")
when i first tried these ili9341 screens, it was with a 2.2" and i encountered issues with the speed and what it could handle (69000000 max)....
moved up to 2.4" and less of an issue and the 3.2" i've really had not issues with at all.....


i havent got around to overclocking the setup with the 3.2" yet, so it will be interesting to see how it fares....
but even at around 30fps is not bad (espcially that at least the display is clearer)

.

[tinkerBOY]

So I got the old test rig out to test the overclock impact on screen speed. Used the overclock settings I found here
https://github.com/RetroPie/RetroPie-Se ... erclocking

So we've up adding this to the config

arm_freq=1000
gpu_freq=500
core_freq=500
sdram_freq=500
sdram_schmoo=0x02000020
over_voltage=2
sdram_over_voltage=2

And things broke

IMG_20171017_214827.jpg

Dropped the speed back down to 80000000 and the screen worked again, but the debug messages were flicking round 33fps still!

It's weird though, even when it's too fast for the screen to cope, it still doesn't get over 33fps

i think 33fps could be the max these screens can push/handle.....

i also have a feeling (and its an ignorant feeling) that the bigger the screen the more you can throw at it (ie 2.4". 2.8" & 3.2")
when i first tried these ili9341 screens, it was with a 2.2" and i encountered issues with the speed and what it could handle (69000000 max)....
moved up to 2.4" and less of an issue and the 3.2" i've really had not issues with at all.....


i havent got around to overclocking the setup with the 3.2" yet, so it will be interesting to see how it fares....
but even at around 30fps is not bad (espcially that at least the display is clearer)

.

I hope you're right with the bigger screen being better coz i was immediately disappointed with the two 2.2" spi screen i bought. Although i tested them using just jumper cables. I doubt if soldering directly to the pi would make a big difference.

Will try some bigger ones.

[moosepr]

@veterangamer I was actually testing this on a 2.2 screen. I would assume they would all be the same, the only difference between the screens should just be the size of each pixel

@yaya my main drive to go faster was bragging rights, but also I thought if we could get the speed up, it might help reduce the tearing that you get on full screen changes. I agree that 30 plus is more than ample!

[YaYa]

The tearing is more a synchronization issue than a FPS issue.
To avoid tearing, the output of the screen must be well synchronized to the buffer’s output...
In short, i think i would be better to force, lets say, display at 30fps flat rate and prevent bumping lower and prevent bumping higher.
At least this is how i was dealing video effects few years ago, before we went HD.

[tinkerBOY]

Are there other ways to use the screen on the software side other than fbcp?