[Arm-netbook] My little idea...

[Christopher Havel]

I'm... I'm blown away. YOU guys think MY stuff is awesome...? Holy 
/crap/. I'm the smallest fry in the bin.

I've got a lifetime total of maybe an hour of futzing with 
microcontrollers -- and I'm being generous there! 90% of what I know how 
to make is discrete logic or transistors-only or relay crap. Probably my 
most complicated circuit ever is a relay adder-subtracter that has a 
rotary phone dial as input. (Never have been able to build it -- I'm 
actually fairly poor so being able to build anything is an event of 
near-legendary proportions...)

Seriously. I'm the sort of electronics hobbyist that has to look up 
circuits on the 'Net and then tweak them or combine them to get what I 
want. I'm not sure I'm even qualifiable as "little league" here -- I'm 
the hardware equivalent of a script kiddie, maybe. I think I might 
actually be a level or two below that...

The schematics that you say are "awesome" are a combination of six parts 
Wikipedia, five parts general Internet (with tweaking), one part 
pinouts[dot]ru, one part from a Forrest Mims book, three parts sheer 
unadulterated guesswork, and two parts straight off the EOMA-68 wiki 
page. I can't say myself if it's awesome or not, but to me it looks like 
a total kludge :P

Oh yeah -- one idea I had to make assembly even easier (definitely need 
a PCB for this, hand wiring it would be a nightmare) -- socket the R-2R 
ladders -- so one DIP-16 socket for the input 2Rs and another for the 
column of Rs and the 2R at the end. Makes things more compact, and it's 
super easy to replace resistors if they're faulty someday.

If you can link me to the Olimex schematic, I can try to understand it 
and adapt it, but I'm not promising anything. I'm a very visual person 
so words describing it will probably not work anywhere near as well -- 
I'll probably just be extremely confused. I can look up pinouts and read 
datasheets and put it together like a jigsaw puzzle in my head, and 
that's the best way for me 'cause that's what I'm used to ;)

On 10/16/2013 5:02 AM, luke.leighton wrote:
> chris this is awesome.  suggestion: if you have the experience and
> knowledge could you look at selecting and designing in suitable
> buffers on the RGB/TTL lines?  there's a schematic from olimex which
> does this (doesn't use R-2R uses 1x 2x 4x 8x etc. resistors) which i'd
> like to use but it's an "attribution" license which is incompatible
> with the GPL.
>
> l.
>
> _______________________________________________
> arm-netbook mailing list arm-netbook at lists.phcomp.co.uk
> http://lists.phcomp.co.uk/mailman/listinfo/arm-netbook
> Send large attachments to arm-netbook at files.phcomp.co.uk

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.phcomp.co.uk/pipermail/arm-netbook/attachments/20131016/ca8d3568/attachment.html>