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Reverse Engineering the Macintosh SE PCB & Custom Chips for 1:1 reproduction

Well, they're here.... GND tests show... THE EXCLUSION WORKS!!!  The rear I/O should now be good to go, it's not shorted anymore, and the rear ADB and serial ports are grounded correctly now. 

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OK - i found a supplier of DB19F connectors for PCB's - exxos store! The Atari community use them, too - i bought a few from there for the SE's :)

 
OK - i found a supplier of DB19F connectors for PCB's - exxos store! The Atari community use them, too - i bought a few from there for the SE's :)
yea, I think it was a group effort with Steve Chamberlin, and a few others to get those DB19's newly manufactured. 

I think it was the male side, but I cant remember exactly. 

 
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yea, I think it was a group effort with Steve Chamberlin, and a few others to get those DB19's newly manufactured. 

I think it was the male side, but I cant remember exactly. 
Yes, male solder cup connectors only. I was quoted a minimum of $25K to do the female board mount version... 

 
In regards to the RTC replacement. If you have to build an adapter board anyway could you not just put an RTC chip + translator AVR on the board. Use the RTC to keep time then the AVR for PRAM + comms translation. If a pulse is needed pick one with that output and map it to the pinout.

Totally speaking off the cuff.

 
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RTC chip + translator AVR is indeed totally another possibility that would allow for using ATTiny85 in one of the smaller package sizes.  I'm guessing the main benefit of this layout would be potentially reduced power consumption... due to the increased complexity of having two chips rather than one, I'd guess that's something only to investigate if we're having trouble with the ATTiny87 consuming too much power in sleep mode with the asynchronous timer.

In any case, (1) if you simply want to get a bootable Macintosh with a reasonably well functioning RTC, the ATTiny85 approach should ready to go, (2) getting accurate time entails ATTiny87 and adapter board, and (3) there may be a final upgrade if we want to reduce power consumption.

 
Yes, male solder cup connectors only. I was quoted a minimum of $25K to do the female board mount version... 
Wow!  I had no idea those were that expensive.  I'd almost thing it would be easier to engineer new tooling and do it yourself or hire someone to assemble.  After looking at it, I'm sure its <$5000 in tooling.  Such a crazy thing to be rare.  I truly had no idea. 

 
@Kai Robinson cool!  He has a great channel, and seems like a cool guy!  I have one of his calendars that he was selling for charity last year hanging on my wall

@Phipli just noticed that! nice little easter egg

 
For the FDD connector, why not alternate thruhole rows for a 20 pin Female Edge card connector with the standard 19pin D-Sub? That way DB or Edge Card connectors could be installed. Development of any future FDD doohickies could use edge card connections for tighter fit to the case sans connector part count.

FloppyEMU adapter like BMOW's would be soldertail DB sandwiched to 20 pin edge card PCB to rather than DIP header.

yellowstone-db19f.jpg.d0013f2d980612e14a48bf3a8f607f9a.jpg


https://www.sullinscorp.com/drawings/54____C___DRA_,_C10876-E.pdf

Connector in PDF has threaded lug mount option

2-54mm-Card-Edge-Connector-Right-Angle-DIP-Available-for-Different-Poles-PBT-Selective-Gold-Plated.jpg.f8d3cdace80f7b24e6b90398fcbe578b.jpg


 
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