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FarmerPotato

Bringing up "Geneve 2020": Debugging Help Please!

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I am starting a new thread to ask questions that come up during debugging of Geneve 2020. I appreciate any insight that anyone can give!

 

The status at this point is that I have a backplane, with cards for CPU and some Flash ROM and RAM.

 

However, last night I replaced the crystal with a 12MHz in order to run the memory bus at 3MHz. Then I turned it on. Nothing. Horrified, I saw I had my supply set to 6V.  I changed to 5V and checked CLKOUT. Nothing. Last time I checked, it was a steady 6MHz, now I expected 3MHz. 

 

Have I fried the 99105 CPU by applying 6V? This is the ceramic TMS99105AJDL, date code 9123.

 

By itself, the CPU card is consuming 350mA, as it did before. The memory card adds 350 mA. No CLKOUT, 0V on XTAL1, 5V on XTAL2.

 

I desoldered the crystal and put the 24MHz back in. For a while I got this clock. Then it flatlined and now it consumes 700-900mA.  Generally the outputs show a flat 3.6V.

 

Ideas?

 

BadClock.thumb.PNG.fae57311d524f830f029adf44678977c.PNG  Vertical scale is 5V. So bad undershoot. From 4V down to about -2V before reaching 0. The signal is driving one input of a '645.

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Doesn't sound good... Dunno about the 99105...

 

However, once upon a time... I inadvertently reversed the high/low AC voltages feeding the P/S, on my new used 4A. It seemed to be running ok. I left it on, unattended for some time. When I returned, I could smell the magic immediately! It was dead.:skull: After disassembling, I found the sound IC had disintegrated, burning a small hole through the PWB. I found the 5vdc regulator shorted, allowing approx. 18 volts DC onto the 5v rail! After cleaning thing up somewhat, surprisingly, all was well, sans sound!

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On 10/12/2020 at 8:01 PM, HOME AUTOMATION said:

Doesn't sound good... Dunno about the 99105...

 

However, once upon a time... I inadvertently reversed the high/low AC voltages feeding the P/S, on my new used 4A. It seemed to be running ok. I left it on, unattended for some time. When I returned, I could smell the magic immediately! It was dead.:skull: After disassembling, I found the sound IC had disintegrated, burning a small hole through the PWB. I found the 5vdc regulator shorted, allowing approx. 18 volts DC onto the 5v rail! After cleaning thing up somewhat, surprisingly, all was well, sans sound!

Pretty hairy, burning through the 76489 (or 94624 depending).

 

I'm re-testing my CPU on a breadboard. It might be that my cpu board has some fried chips. Maybe they are dead and just putting a lot of capacitance on the cpu pins.

 

jbdigriz has sent me 2 cpus and I got another from polida2008. I'm into the testing.

 

 

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Does anybody know about wire wrap bits and matching sleeves?  I'm trying to get a pair, at an affordable price (say $25 each)

 

If  want to learn something about wire wrap, for constructing circuit board prototypes, try these great tutorials:

https://www.specialized.net/tools/wire-wrap-tools.html

https://docs.rs-online.com/dc28/0900766b80565423.pdf

 

YouTube:

 

 

 

So:


I have a Cooper Tools electric wire wrap gun. I have one bit, one sleeve, which don't work together. I need a bit, and a sleeve to match. Without that, I'm using my long-time Radio Shack hand tool (the kind that looks like a screwdriver.) 

 

TI used wire wrap for PLCs and stuff, I guess, from the junk in their dumpster.    When I was 17, a TI engineer loaned me a gun with cut-strip-wrap CSW bit, which was a breeze to use. I will settle for just a wrap bit/sleeve!

 

Here are the parts I've found so far on the internet:

 

30 AWG wire, mostly 6-digit Cooper tools brand part numbers:
 
Summary     Bit             Sleeve
       Have 501097 bit     Need 507100 Sleeve (Cooper) UPC 960948
       Need WB3032M        Have P3032 Sleeve (these are brand OK Jonard)
ES    Found 511395
ES     gone 507502
ES    Found 990063 CSW     Need 990064 with cutter and exit slot     UPC 960740                 
AP    Found 990063 CSW
AP    Found 990764 CSW     Found 990765 CSW

VERY LARGE TERMINALS - 0.066" (want 0.031 diagonal of 0.025 post)
AP    Need 501194 UPC 951908 Found 502129 (normally 24-26 AWG)
AP   Found 507063
SP   Found JDV bit SP 53110, $30.50, .047" bit radius, thats .094" diameter, huge

abbreviations
 J    Jonard
SP    Standard Pneumatic 
OK    OK Industries
ES    https://www.electronicsurplus.com/
AP    https://store.armyproperty.com/
SP    https://www.specialized.net/tools/wire-wrap-tools/wire-wrap-bits-sleeves

 

 

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Well dang... I searched for 507100 yesterday on eBay and there weren't any bargains. Then last night, I saw a seller added more inventory,

including a 507100 and SB30xxx. $24 and $12. The top two on my "needs" list.  So, I will have 2 matching sets of bit +sleeve. 

One set of Jonard brand, and one Cooper Tools! I feel lucky.   It is personal tools from a retired EE: tools going back to the 70s.

 

Wire Wrapping Sleeve, 507100 by Wi

 

Wire Wrapping Bit, SB30MSH-B by OK M&T, 30 AWG

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