[v1.2] MECB OLED Display 128x64 Card

[Editor]

An all-in-one 128x64 OLED Graphics Display Card for the Minimalist ECB.

I've always enjoyed playing with OLED display panels, with their sharp clear pixels, and inky blacks. Unlike LCD, where backlight driven displays turn blacks into greys and colours generally just don't "pop" like they do with an OLED display.

Read all about it here: Minimalist ECB (MECB) – OLED Display 128×64 Card

[epaell]

Works a treat

It's quite a fun little device to play with ... but really hard to get a good photo of. Each line is at a different brightness but really hard to see in the image.

[Editor]

It's quite a fun little device to play with ... but really hard to get a good photo of. Each line is at a different brightness but really hard to see in the image.

Looks awesome! Your photo came out great, and I can see the increasing brightness of the lines.

I'm still having lots of fun with mine, but (as usual), I'm also juggling multiple projects.

It looks like you went for a 5x7 font, for a 21x8 character display?

I was thinking it would fun (someday), to implement a replacement CODTA routine to direct ASSIST09 ouput to an OLED display driver.
A few other mods would be needed (to allow for the shorter line length etc.).
But, this could be an option for a nice stand-alone 6809 setup (with just a PS/2 keyboard).

Of course, you'd probably also want to add a way to Load / Save from a memory card...
But, than again, I do remember back in the day we just lost everything when the power was switched off (and re-entered it next time).
LOL. How did we cope???

[epaell]

I actually pilfered the font that was originally used for the TMS 99x8 (which is 6x8 to achieve the 40/80 character wide display on that). It's nice how you can set up row and column extents on the device - it makes it a lot easier to simply dump values to the device and have it come up as a character.

I too was thinking about modifying the output routine to allow output to either this device or the TMS 99x8. I was initially working towards the TMS 99x8 and got as far as getting most of the character writing happening (and emulating a flashing cursor - done in the input routine to avoid having to mess with interrupts) and just needed to add a bit more logic to detect when it goes off the screen in order to initiate a scroll ... but haven't quite had the time to get back to it. Then, of course, I got distracted with a shiny new toy (this OLED display) which also got me messing about with the text output ... and I was thinking of adding a Breseham line-drawing algorithm but once again running out of time - I had a prototype working in Python but now need to translate it). Sigh, too many half-finished bursts of coding.

I still need to get around to getting a PS/2 keyboard for my set-up but it does have a load/save via the microSD card. The downside is that in order to use it I need to boot into FLEX or nitros9 (those also have assemblers and high level languages but I'd have to admit that I don't have the patience to use line-editors anymore - so still prefer to develop on my laptop and transfer code across). I agree though, it would be nice to have it all self-contained ... and it does bring back memories of heart-ache when finally getting some really complex bit of code running only to have the power fail (usually because it was such a hassle to write regular versions to cassette) or changing it slightly for that final touch only to have it corrupt the memory. We're so spoiled these days and wonder how the heck did we do anything back then given all the limitations.

[djrm]

I do like the look of these OLED displays, they fit nicely on the MECB cards too.

... and I was thinking of adding a Breseham line-drawing algorithm but once again running out of time - I had a prototype working in Python but now need to translate it). Sigh, too many half-finished bursts of coding.

I have Bresseham line and circle drawing functions in C which use a single point plot function to write to the screen. Should be portable to other systems, I have used then in several systems. I can't remember where they came from now, they have no bugs that I know of.
Source at line 542 here: https://github.com/DavidJRichards/SC126 ... 6963_lcd.c
Used to draw this image:

t6963_lcd-clock.png (160.05 KiB) Viewed 3668 times

I have some 3D transform functions somewhere which can show nice animations, I'll have to dig them out.

hth David.

[epaell]

Thanks David,

When I get a chance to work on this again I'll have a closer look. Even with C I'd still need to translate into 6809 but thankfully the algorithm is relatively simple enough.

[epaell]

Yay, basic line-drawing now working - not the most optimal code but at least it seems to run.