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Re: [N8VEM-S100:2419] Re: 6502 CPU Board V1 components question



On Monday, February 17, 2014 1:37:58 PM UTC-6, Fabio Battaglia wrote:
Gosh, this made my day!
A very amusing read, thanks to have taken the time to write it instead of just saying "yeah, just put in those 1k5 and stfu" ;-)

LOL yeah I've been mulling over in my mind the idea of volunteering to spend endless hours editing the EDA files, and implementing some universal standard across all the layouts.  For example some boards have mixed formats where some resistors are like R82 and others are like 220 aka 220 ohms and you have to start following traces if you want to figure out the resistor ID.  Also I'd go thru and make all the non-criticals show a range (I was thinking 820-2200 for the stereotypical pull up) although of course there are sorta critical values like LED dropping resistors.  Same deal with cap values, leading to my careful study and comparison of mfgrs different reg data sheets and the like.

Would it be a problem if the dropping resistor for the board select LED was labeled on the silk screen as "board select dropping resistor" or whatever?  Or a line between the LED and its resistor?  Little things like that.

Another infinite spare time exercise for either myself or another sorcerers apprentice type who knows just enough to be dangerous would be modding all boards regulators to layout for both unobtanium TO-3 regs and modern TO-220 regs.  I have two Z-80 boards on my desk that need bodging to use TO-220 which is not a huge deal, but it would be nice to just drop in modern regs.  Or just wave a fond farewell to the TO-3 and stick to modern TO-220 3 amp regs like the LM323T.

Another infinite spare time exercise is standardizing option pin header names and labeling, and especially LED naming/labeling.  Like across the platform the 7th option header will always be P7, and every "board select" LED will be labeled "Board Select (blue)"  Exactly, on all boards.

Almost all boards have space somewhere to put a green 5V power LED.  I'd like to know for troubleshooting if a reg fails open.  And it would look nice.  Thats probably an ambitious goal given my EDA experience.

The standard cap spacing is I believe 5.1 mm but there's a narrower spacing available.  Especially for regulator caps there's ways to fit multiple cap lead widths...

Someone who knows what they're doing needs to design logic, place chips, route traces.  But a sorcerers apprentice type (like me?) could handle mere cleanup and labeling.

This is one of those, do I really have the spare time, do I really know just enough to be dangerous, does it really have to be done?  But I think about it anyway.