开云体育

Hello,

This email message is a notification to let you know that the following files have been uploaded to the Files area of the [email protected] group.

Uploaded By: David S <dsatn04@...>

Cheers,
The Groups.io Team

Hi all.? A belated Happy New Year.

There's been quite a few requests for help with the TFT for the V6, the ones available in the wild are hit and miss.? I've now got 5 of the 2.8 TFT obtained from 3 vendors over the last year or so.? They seem to be the worst thing out at raising ones blood pressure with frustration trying to get them to operate correctly.? Of the original 3 only 2 will ok correctly with the Blue Pill yet all of them are fine with a Teensy 3.2.

I have also been watching with interest progress of the code for the V5 and then the V6 with a view to upgrading my early V3, more frustration with both types of display.? The TFT would be a great addition, so that's the way I'm going,? hence ordering some new versions. I've spent a troubled few days trying to coax one of the TFT's no go, the code assembles loads correctly,the display is wired up ok, I know it functions with the Blue Pill so back to basics.

I tested the TFT with a level converter, easy to do and magically it functions. So her's my thoughts to share with others it may help. You can find the schematic here??/g/BITX20/files/V6%20TFT%20Adapter

This is intended hopefully to assist with the problems encountered when trying to obtain a suitable TFT to use with the Ubitx V6 code.? Very many of these displays available from China are advertised as 3.3/5v (operation ?), they will run with either a? 3.3 or 5v supply but will only work with 3.3v logic signals. When wired as in V6, and running the code, the display will show only a blank white screen.

?

The idea is that this should act as an interface directly between the lead from the raduino and the actual display in use, no messing about with your Raduino.

Hope this is helpful to someone.

David S

Excelent work and much appreciated. Been really struggling with this on a V5 and this will fix it.

Thanks again

Best Regards

Brian_____MM0BEF

David,
Looks like you have the L78L33 regulator wired incorrectly in the schematic.? You want Vin from 5V Raduino to generate 3.3V for the LV side of the level shifter.
Why supply the display module with 3.3V derived from the same 100mA regulator instead of using the? display board regulator?? I'd understand if trying to beef it up and have better cooling.
The level shifter from 3.3V to 5V (raduino) is not needed as the VOH meets VIH requirements.

Thanks Gary,
David has fixed the error. Some of these displays dont play well with the onboard 3.3 regulator. Bypassing it and using an external 3.3v regulator eliminates any potential problems there.

Regards

Brian_____MM0BEF

Hi Gary

Yes sorry the regulator backwards, my bad eye's and late at night I missed that, all fixed and the new version uploaded.

Why use an additional regulator.? It's the backlight that draws most of the current that remains on the 5v rail through a 22 R, I wanted to minimise the possibility of "operator error" having people break out the 3.3v from the Nano.?I've got a Ubitx V3 MM0BEF has a V5, neither has the same wiring loom as the V6 but even that does not have 3.3v on the display cable.

This was not intended to be a project, just a guide for people who are having the issue of sourcing? Displays either as replacement for the V6 or to upgrade earlier versions.? I cant see any source where your sure your going to get a Display that works correctly.no messing.

HTH.

Regards
David S