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- nobody knows. Or if they do they are not saying. What a mess. Sometimes the 'wisdom of crowds' leaves a little to be desired. I work n a post-office and it might cause chaos.. We might have to go through it all over again with Scotland and Indyref2 :cry: - but I think there are far more important ...

Hi, In the meantime - I did this ST7789 code - here -https://www.matrixtsl.com/mmforums/viewtopic.php?f=77&t=22377&p=104068#p104068 - which has a 'bitmap' copy. For monochrome displays you'd just need the 1 bit version. This is (hopefully) a bit easier to follow than reverse engineering the FC compo...

If you send me one of the displays I'll have a go....
Just been doing a st7789 (spi) display - which works (at least on some displays )
The source for the ssd1306 has been published and it shouldn't be too hard to modify for the different resolution..

Martin

On the ATTiny85 (and possibly other ATTinies - not checked) SPI (USI) doesn't work in hardware mode. With 'Channel1' - SCL gives a clock signal but no data is output on MOSI. Using 'Software' (and all other things the same) - MOSI outputs data.. Note that it's probably not much slower (403kHz / 410k...

Phew - not much progress. Messed up one display trying with resistors.. Just had a play with with an ATTiny85 (which should run at 3v3) - but although SCL seems good, there doesn't seem to be any signal on MOSI. So no joy. Anyone used SPI on the ATTiny85? Took a long time to get a USBasp programmer ...

Not yet - it's a very nice display.... Easy to work with too when it's working

I'll hopefully have a bit more time to play over the weekend - and I've just received a 3v3 usb-tiny (alike) from Bangood...

Martin

Sounds like the upload is failing for some reason.

It's getting com 6 - is this the correct port ? (Good to check - see another thread about FC sometimes attempting to write to the string com port)

Martin

I wired a working display with 2k2 resistors on all the data lines - signals looks ok on dc and SDA but clock doesn't work - I checked with oscilloscope.. either signal is too fast for a resistor reduction, it or the resistor is faulty (maybe my soldering?) No joy - yet.. the 'newer' type displays I...

Today I'll try with resistors..
I can't get the new displays to display anything - I tried fast library, adafruit library too without success - maybe my soldering? Can you point me to the examples you are using.
Maybe some differences - there seem to be 3 versions in the datasheets..

Martin

And I think I've found the problem.. There seem to be'variants' of the display. I have two, which I will call the old displays - the screen print on the back is poor quality and some 'new' displays with much better printing. The 'old' displays work perfectly, and the new ones not at all. I tried two...

See PM for suggestion...

Hi Bill, The Uno is one of the free targets - so yes, you'd need to buy the Arduino pack to use the Mega... First, though, is it possible to 'trim' your code to fit. (I once went to a lecture where it was asserted that all programs can be optimised by (at least) one instruction - this of course lead...

A frustrating evening.. Nano ran happily all day (and display restarted after a power cut). Slightly worryingly - my bedroom hit a 'peak' of 12.6C. Toasty... But my attempts to get a 3v3 Micro (Pro) running failed... Might be easiest to use an ATTiny85 running at 3.3v - but my USBTiny is v1 and 5v o...

I've set up the thermometer (and added humidity) on a long term test for today... Tonight I'll try with a 3v3 MCU... Try adding a smoothing capacitor across VCC/GND? I don't think a Nano is significantly different to a Uno - both should be able to supply 50ma on the 3.3v pin (and possibly up to 150m...

As a thought - the display seems'sensitive' to fluctuations in power - if I touch the 3.3v connector then it often make the display fail. Perhaps s capacitor and maybe a separate 3.3v supply (not sure how much per a Uno 3.3v pin can supply?)

Martin

disp.jpg Almost done now.... Something odd that it's not starting reliably for you.. Seems rock solid on a Nano... I did a quick thermometer with a DHT22 - but missed on the 'degrees' symbol. Martin st7789.fcfx Just with temp added (DHT22 on d2) - still displays rainbow, lines and text before swapp...

Hmm - I've just downloaded on a different computer and all seems well. Can you make previous version work still?

Martin

Wiggle those wires - you should be getting rainbows, lines and text too...

Martin

Hmm - Orientation is the tricky one.... Still some more to test.. I added some text routines. Print - is slower, but allows the text to be scaled and - it 'wraps' - so it goes to a new line if the text overflows the current line.... Not drawing the background (for example on a clear display) saves s...

Maybe - but a way to go before that's a thing...

What features do you need / would you like?

Need to get text working..

Hooray, glad to hear it's working!

I've just worked out the real reason the bitmaps are reversed - my FC is making up for deficiencies in the python script - which reverses the lines (vertically) and also horizontally...

Next version soon...

Well that's the left to right issue sorted for 1 bit bitmaps... Note that bitmaps are stored as dwords (32bit) - so rows are always a multiple of 32 bits long. This means it can be quite wasteful of memory (so a 8x8 monochrome bitmap will use 32 bytes (rather than 8 )) The code here - uses bitmap fo...

Sounds like your having good progress. - that's when Jorgen's display starts working too..... :D I added a 'blit' bitmap to display. Here are the 1 and 4 bit versions and a Python script that generates the array assignments for the data and colour table from a bitmap file (need a better way to do u...

Another 'oddity' I meant to check in the datasheet..

The fast library - defines CASET and RASET to be 0..240 (for the whole display) - whereas I would expect this to be 0..239

Any thoughts/guidance on this ?

Martin

One possible change needed - I changed the parity of SCL... To get things working!

Martin