HP 98035 Clock Module Repair-A-Thon - Part 2: HP's Nanoprocessor

[@CuriousMarc]

[Update:] I made a reproduction of the dude's magic pants, as a pair of jogging pants. Available on my Teespring store at teespring.com/magic-repair-pants. If you wear them while repairing vintage electronics, success is guaranteed!

[@MrCarlsonsLab]

Great stuff Marc! Some time back when I was reverse engineering for a company, we would receive punch tape machines to repair, as the customer would still operate their CNC machines from them... And to think, I get hassled about my old XP machine when I show it on camera... LOL. Your video's are always enjoyable, thanks for taking the time!

[@BitKing_Ross]

Both your channel and Marc’s are fantastic to follow, thanks Mr.Carlson

[@SuperAWaC]

There are still a few punch tape CNC machines out there, usually large planers and whatnot. They are slowly being replaced or upgraded though.

[@garbleduser]

This is the brainy interaction I was hoping to see!

[@gymprofessor329]

Ken is honestly incredible

[@jonathanvanier]

Sure is! This channel is simply filled with geniuses...

[@AntonBabiy]

Ooooooo magic smoke! Now you're really teasing us! 😁 Great progress in this episode, often people don't understand just how long it takes. For example what rom you had

[@Consequator]

Electricity is a myth, everything runs on magic smoke because it's not truly broken till you let the magic smoke out.

[@Dust599]

And this is why society is getting dumber.

[@Consequator]

​@@Dust599 'Magic smoke' is actually a common joke during electronics classes in school, at least it is here ?

[@tekvax01]

@@Consequator that... and which ways do the electron holes travel?!

[@gtb81.]

@@Consequator also, don't flip it upside down or the electrons will fall out

[@mmmyke1784]

It always amuses me how organized you work. I should learn that...

[@CoreyStup]

The physical notebook complete with pasted in Xerox copies of tables and other documents is a great idea.

[@derkeksinator17]

When in doubt, document.

[@NivagSwerdna]

Well you have to admire HP engineers for creating a watch button pressing gadget to get the job done! The reverse engineering of the nP was really interesting... cannot wait for the next episode!

[@AllElectronicsChannel]

Man!! The idea of using a clock chip and toggling the menus to set the clock truly show how HP was ingenious!!

[@mushroomsamba82]

You guys are so brilliant preserving all this stuff. Things progress so quickly it's easy to forget these relics are an important part of computer history.

[@GavinR824]

Never have I been entertained so much by a technology video I barely understand.

[@acmefixer1]

@CuriousMarc Treat the IC pins as if they were sacred. Never bend the IC pins. Put the IC into an appropriate socket and then bend or modify the socket pins. If you need to make somewhat permanent changes to the pinouts, stack *two* sockets on top of each other and make the pin modifications between the two sockets. Bend the socket pins out and solder 30 AWG wire wrap wire between the upper and lower socket. Then put the ROM chip in to the socket stack and put the stack into the ROM reader. Voíla! You now have a socket than can accept the EPROM, so you can burn the ROM code (with code changes) into the EPROM and it will work in the ROM socket. We used to do this to the Apple II ROMs to get to the protected game code. ;-) I think I said this in the first episode. There was a circuit that shut off the ROM's positive voltage until there was a stable negative 5V on the ROM's -5V pin. The ROM can draw excessive +5V if the -5V is not present. The only time I bent the IC chips out was when two EPROMs were stacked one on top of the other. We used two 2716s to substitute for a 2732 by stacking them on top of each other and rewiring the CS and NOT CS chip select pins so either the top or the bottom chip was selected.

[@CuriousMarc]

You guys are so hard core! Sacred pins! Holy extender cards! But we do Voodoo electronic repairs, pin bending and PCB cutting is part of the cult. Some say we even put pins through capacitors.

[@ScienceANDesign]

@@CuriousMarc Voodoo electronics..!! This is going to be the name of my next enterprise!! Awesome..!!!😎 tnx Marc..!!

[@johnopalko5223]

@@ScienceANDesign You can relocate to Portland, Oregon, and open a shop right next to Voodoo Donuts.

[@fburton8]

Was the bent pin okay in the end?

[@CuriousMarc]

@@fburton8 Yes it's fine, back in the socket. The pin thanks you for asking!

[@fredflintstone8048]

You have a great team of friends. Ken and the rest.. I admire the knowledge and abilities that you all have and how you all come together for the various projects your team takes on. I'm always pleased when I see a new video from you and your group and jump right to watching ahead of all the other channels I'm subscribed to.

[@CuriousMarc]

Thanks 👍

[@TheJimbodean67]

In 2107 people will be watching an AI version of CuriousMarc dissecting a liquid suspended nanobyte run quantum computer neural interface with ftl capabilities designed for communicating with the colony on mars. Love to watch you break down the engineering! Thanks for sharing your time and diligent work.

[@edgeeffect]

That "mess" of jumper wires and test connectors looks fantastic... this is one of the best hacking adventures I've ever seen on KZbin...... or in real life. Can't wait for the next episode.

[@TheDefpom]

Very impressive that you got the code and chip reverse engineered.

[@warup89]

Watching your videos gives me the same enthusiastic feeling towards learning as I used to get back when watched The Discovery C., The History C., ect. When, well....they actually showed informative content. Kuddos+

[@Dust599]

You are exceeding good at the cliffhanger, you have demonstrated this many times, please desist from future examples!

[@deviljelly3]

Loving this series sooo much. I think it's time to recreate the nano processor and clock chip in an pla/cpld/fpga/atmel.

[@tekvax01]

Not it...................... :P

[@senilyDeluxe]

Let's create a 1970s video game console using this CPU!

[@ckm-mkc]

I gotta say, what you are doing reminds me of the old Silicon Valley - I was explaining this to my wife and she said "it's like Xerox PARC back in the day" - thanks for reminding me....

[@ScienceANDesign]

CuriousMarc: Second 1: yep, I've just read the code from the ROM chip. Second 2: Well, I've disassembled the code, completely understood to the very last bit and commented it. Me: Second 1: well, this is some chip, I don't know what it does. Week 2: I think this is a ROM chip. Week 7: I've managed to read the ROM chip. Month 3: I think I understand this code Month 4: No, I didn't Month 6: Well, I understand some parts of the code (maybe 60%). Month 7: Ok, I give up, this clock module is a f&$&# piece of s&@#..!!! Gosh, I want my seven months back😭

[@kevtris]

it might be a good idea to put a zener diode across the battery so when it dries out again in 20-30 years it won't blow up the probably 100% unobtainable clock chip in 2040.

[@video99couk]

I mentioned this on the last video, and it was correctly pointed out that a zener won't do it, it would leak too much. But a zener could be added to the charging circuit, behind a charging diode, and that would prevent further blow-ups.

[@electronash]

By 2038, we'll all be too worried about the "Linux time bug". lol

[@teeroy766]

I'm hoping by that point that manufacturing might have improved to the point where we can 3D print replacement chips entirely, or at least there would be companies who could do it.

[@greendryerlint]

@@electronash I'm hoping that civilization is still around in 2038, or heck, that I'm still around for that matter..

[@electronash]

@@greendryerlint Same here, tbh. It's not been the best of years for most people. lol

[@PapasDino]

And thus appears "the Magic Smoke"! Thanks Marc, great series.

[@PixelSchnitzel]

Absolutely brilliant. Marc, your videos always inspire me to get back to work in my own lab! Thanks for the extra energy shot!

[@ravegirlcyan]

The Final Fantasy music genuinely made me think I still had the game open in the background twice before I realised it was just the video.

[@glitch1299]

what song was that I can't remember which area it was from...

[@greendryerlint]

Truly some uber troubleshooting and reverse engineering. Great video. It's good to see someone that cares enough about this old hardware to understand and resurrect it. I guess it was easier to engineer it to get the time by using the set button and get it 'serially' instead of just reading each digit, though seems like a Rube Goldberg way of reading the time.

[@charliepanek8481]

A cameo by the HP3585A, which had just been released into production at HP in Loveland, CO, when I started working there in 1978. It contains the "BUFFLO" decimation filter chip (Barely Usable Fast Fourier Like Object"), designed by the legendary Lou Scheffer. Those were the days..

[@eliotmansfield]

good stuff - that clock breakout is very clever

[@sanityd1]

I had wondered why they don't exist...of course they do!

[@chriholt]

Absolutely amazing stuff Marc, I'm really enjoying this series!

[@jeremiefaucher-goulet3365]

I only come here for the music in the intro ;-) Just kidding, but the music is really great!!! Looking forward to see all that hard preparatory work put to good use :) I expect no less than 100% repair success rate.

[@JoeMcGuire]

Absolutely amazing video Marc! Ps, loving that Blue Angels watch!

[@EngineeringVignettes]

Looking forward to checking out what Ken found in that nano processor. Might be fun to try and emulate it in a small FPGA or even a CPLD. Also got a special treat when I realized that I have the same breadboard as you, albeit one that I bought from Jameco many moons ago. Thanks for the updates, very good content! Cheers,

[@justjoeblow420]

We may still be waiting on Smellavision but I could smell that magic smoke from here through my LCD.

[@BlackEpyon]

It gave up the smoke.

[@greendryerlint]

Future electronics won't use magic smoke. They will have magic vape instead..

[@mymessylab]

As ever great video, but the smoke at the end of the episode is Magic 😬😬.

[@jpipod1]

I have come to love your videos. And are the highlight of my week when there's a new one.

[@growingknowledge]

Release the smoke...fantastic detail and explanation as always. Thank you.

[@randomelectronicsanddispla1765]

That was an awesome nineteen minutes and thirty-one seconds cliffhanger!

[@appliedengineering4001]

To answer your question @6:13 in the video. The reason they put that loop-thru on the chip enable pin is to protect any battery-backup ram from being corrupted by sporadic voltages caused by the inserting and removing of the cartage. If you look at the edge connector. the 2 pads on the male end should be shorter the the others. if not? On the female end, the contacts should be recessed into the slot more then the others. The idea is, is to make it sure that the those pins are disconnected first and connected last. Why they have it connected to the ROM only? My guess is that the ROM may have been substituted for a battery-backuped static RAM chip at one time.

[@bertholtappels1081]

Fascinating. Especially the mask ROM chip select is an important piece of info that may be very valuable for me some day.

[@tonybell1597]

Thanks Marc, love this series.... fascinating ...

[@nin_ocho]

Is that the Ruby Sea theme I hear? :^D Great video as always Marc, dearly loving this process.

[@RobSchofield]

AAGHH! Don't leave me hanging!! Great bit of analysis. Am particularly impressed by Ken's work. Which division of HP produced the nanoprocessor? It sounds vaguely similar to the processors used in their pocket calculators of the time.

[@MrMaxeemum]

Fascinating. I truly love watch your videos. Thanks

[@2packs4sure]

I changed the button cell in my old Radio Shack calculator the other day and I modified it slightly to use a battery I already had so I'm pretty much on CuriousMarc's level now....

[@senilyDeluxe]

Super rare undocumented Thing (this time it's some unobtainium ICs that time forgot) -exists CuriousMarc&Ken Shirriff -Let's reverse engineer every last bit out of it! Me -Guess it's time to make a retrocomputer using one of these :-)

[@SeanBZA]

Going to guess the rom select going out was to allow the main board to have a rom instead of the clock board, so that you could reuse the clock board in later models with a new rom to add extra functionality and have the original board as a drop in part with no rework required. Also could have been used on the assembly line to run diagnostics in a separate chip to do a diagnostic while the unit is complete, and then the diagnostic rom stays in the test fixture instead of having to pull the rom out and replace it.

[@0xbenedikt]

That’s probably the reason why. Nice reasoning.

[@dwaynetube]

At the part about the extender board, when you said "...to take good measurement and then to cut this..." my first thought was "Are you crazy??!!? You will have the other instrument eventualy and then you're missing the extender board!!!" :-) :-) :-)

[@CuriousMarc]

You can just use the two parts of the board together again.

[@dwaynetube]

@@CuriousMarc Yeh, after that spontaneous thought I was quite sure that you would figure something out to remedy the cut. OTOH its not in mint condition any more :-)

[@JATmatic]

Oh no! That ending of magic smoke escaping.. :D

[@jeroenbogers8825]

Thank you for the very interesting video. Always cool to see how technical challenges were tackled in the old days (and how that may have affected modern computing) :) Interesting that it never syncs the clock back to the watch chip. I can imagine that when these systems are on for a very long time there will be quite a deviation between the internal clock and the watch clock. Also I wonder if the Nanoprocessor would get the correct minute (or even hour and day) if you power on at second 59 and the watch chip is almost near the next minute (for example at 23:59:59.800)...

[@johnopalko5223]

Ooh, I wonder if they thought of that. Those edge cases can really bite you.

[@DKTAz00]

Who would win? Billions of dollars in research and security hardening, or running your industrial machines on a 70's calculator :D

[@AsbestosMuffins]

6:43 Ah yes the Austrailia Gate, quite an illogical circuit

[@-vermin-]

That's only because Tasmania is missing, again.

[@gmt-yt]

*readies popcorn for next episode*

[@FarzadNL]

@19:20 It seems you found some trapped smoke in the circuit ! good job :D

[@kevinreardon2558]

Can't wait for the next cliff hanger...Wait, that's not a computer term.

[@tonydonnelly]

No wonder HP equipment was so expensive! It seems that it would have to be reset every leap year, since it doesn't have the year stored. At least it survived Y2K and will probably survive Y2K38!

[@tim_bbq1008]

That view of the magic smoke actually caused me to relax...like I just gave up. Can't wait to see what happened. (Like I understand any of it...NOT)

[@oldblokeh]

An oustanding piece of work. Riveting viewing,

[@aaronr.9644]

I see smoke! who doesn't like a good cliffhanger?! :D

[@SuperAWaC]

What the hell? Is that Final Fantasy music in the background? Edit: A-ha. Found it. The title is: 焔の海 〜紅玉海：昼〜. Now after a 30 minute search I can watch the remaining 19 minutes of the video.

[@drakethedragon457]

Back when we needed two circuit boards, a CPU another clock chip and a battery just to tell the time, now we use a single RTC microchip capable of telling and storing the current date and time but still uses a battery to keep time when powered off

[@boris3320]

Ken is amazing !

[@boris3320]

(et vous aussi, Marc !)

[@electrofan7180]

Wow, that reverse engineered mcu and code are really impressive! Now waiting for reverse engineering of magic smoke at the end☻

[@alpagutsencer]

Marc your lab books are looks amazing. Is it handmade ?

[@jpjude68]

mmm i wonder what you're cooking for the next episode! :D that magic smoke seem to signals some apetizing fried chips :p

[@_Tortoc]

Whar are those Number-LED things in the Video? Never seen something like this before but it looks beautiful!

[@meteor8076]

smoke in the end :D :D

[@larryscott3982]

It’s vaping

[@skjerk]

Amazing work!!!!

[@swebigmac100]

This is mind blowing....

[@wonderboy7768]

Mr. Fancy Pants a bit baked keying in those digits. 4:23

[@001snapshot]

You will have to re pressurize the magic smoke containment vessel..:)

[@thierrychampion1972]

Mmmh, magic smoke...Odeur incomparable !

[@madmanmapper]

Imagine it's your job to make a clock module. You make a module that can keep time, but can't store time when off. So you add a bunch of circuitry so that it can press the buttons on a digital watch and read the numbers.

[@HebaruSan]

"We asked the guys from [other department] to provide us an API." (rolls eyes)

[@TreyVaswal]

Seems legit.

[@JonWhitton]

Another great video

[@glenwoofit]

Who let the smoke out? This time it wasnt me. I hope you caught it to get it back in.

[@chrisdickens4862]

O-smelli-scope! I love your sense of humour!

[@clark9992]

I was wondering if it was his own, or was it borrowed. It sounds like something AvE would say.

[@thesnitch7]

6:46 - Where did Tasmania go !!

[@FesixGermany]

Mr. Fancypants stayin' alive

[@johankotze42]

Was that smoke at the very end?

[@Zerbey]

Please tell me your correspondent also wears fancy pants when using theirs? If you yourself do not release a picture in the same fancy pants we'll all be disappointed!

[@coryv3716]

@CuriousMarc Please share which mechanical pencil you use.

[@denisdrozdoff2926]

Magic smoke! magic smoke! let's hope it was all the magic smoke I've seen today

[@rkan2]

Which episode are you making an emulator for the whole module?

[@proudsnowtiger]

The hardest part for me was seeing that double-width riser card get chopped up. Any repair shop will know that riser cards are the most sacred and highly guarded relics in the land. When n cards are needed, there are always n-1 available, and the impetus to steal one cannot be resisted. The riser card hole migrates freely, and always comes to rest with you when you need one the most. You must NEVER loan a riser card: it can in fact never be loaned, only irreversibly donated. Riser cards are irreplaceable. Indispensable. And you just chopped one up. SHUDDER

[@matthewkriebel7342]

I think this one can be glued back together pretty easily. It’s not like he sawed across the traces. Marc is also an executive at a connector manufacturing company, so I’m pretty sure he can make a new one if he really needs it.

[@CuriousMarc]

But the card and I had a long talk beforehand. It had lost its original instrument 40 years ago and was very sad. It was OK with it and so happy to be used again!

[@Broken_Yugo]

Should it be needed I can't see how it wouldn't still work for the original application, no traces between the connectors.

[@proudsnowtiger]

@@CuriousMarc I didn't say you shouldn've done it. I think it was the right thing to do. I salute your pragmatism and dedication to fearless engineering. Still. SHUDDER.

[@Adrian-foto]

Great work Marc, I admire the methodic approach You and Your team takes. I would be curious, if the reverse engineered code reading the clock chip took into account a delay between reading seconds and minutes, when seconds might flip just after it has read them and thus advanced minutes by one and instead of reading e.g. 11:10:59 would read 11:11:59 :)

[@CuriousMarc]

Yes the code takes care of that.

[@LionelG-Euchcat]

Hello Curious ! @15:12 (i 'm not sure why they did that...), I think IMHO that this impulse is the watchdog function of the microcontroler. Why not ? your video's are very interesting, thx

[@swilwerth]

Can that processor be atmelled at this point? I don't want to say the duino part and expend time being sued if I do. Only to emulate the unobtainum parts.

[@CuriousMarc]

You probably want to “FPGA” the Nanoprocessor, and “Atmel” the clock chip. It would be even simpler not to try to emulate any chip and just “Atmel” the whole module. But making a replica/emulation of the Nanoprocessor could be really useful, since the chip is so rare but so many instruments run on it.

[@EdwinNoorlander]

Nice, magic smoke.

[@donfigol8630]

What are the small HP test probes called and where can they be purchased? Many thanks!

[@CuriousMarc]

They are HP 01650-61608 mini-grabbers, they came with their logic analyzers. Mine come from eBay, look up the part number or HP Logic Analyzer Probe Tips. I know they were (and are still) made by someone else and quite expensive new, can’t remember the manufacturer. Best probes this side of the galaxy, highly recommended!

[@DAVIDGREGORYKERR]

if the CS pin on the HP ROM breaks then what about using a piece of stiff copper wire and sticking it in the sock to replace the broken pin and solder a wire to the remains of the broken pin of the HP ROM.

[@paulstubbs7678]

Oh no, the magic smoke

[@itsverygreen532]

The "looped back" CS line is not "wierd" ... the idea is you can connect the board and its ROM bus to an external test card, the CS line can be looped back to run the ROM code on the board, or used to select a test ROM on the external test board, running a long-lost custom test program.

[@CuriousMarc]

I thought so too at first, but there is no connection to the ROM address bus available anywhere! So you can’t connect an external ROM by plugging in a daughter card. Maybe used for exactly what I did? Use an EPROM during development that has an opposite CS polarity from the production mask ROM, and insert a little inverter there?

[@itsverygreen532]

@@CuriousMarc Ah, OK, I understand. Very strange. I was very impressed with the level of effort you went to, I used to work on 70's and 80's equipment for a national broadcaster, lots of TTL logic, custom chips etc but the level of detail you went to is impressive. The disassembler for the nanoprocessor is and incredible effort ..

[@mdijkens]

Hi Marc, Great video again! I've been trying to source the TI-clock chip for some time now, but can't find it anywhere.... Are you willing to sell one to me? (you are allowed to make a profit on it :-))

[@CuriousMarc]

Contact me through my about page (link in the Doodely-doo).

[@radben951]

You don't need one. He's reverse engineered it. You can emulate with another controller and software. Maybe even an arduino.

[@mdijkens]

@@radben951 I can but I don't want to in my retro 70s computer

[@alanroche3872]

Magic smoke! 😱

[@AIM54A]

I see magic smoke!

[@markburton3306]

Fantastic

[@Broken_Yugo]

That is one problem with the TL866 series programmer, the programmer is ironicly not programmable so you have to work around it should you need to dump mask roms. They're so small and convenient though, which is why I assume you didn't drag out some vintage beast of a programmer that can invert a CS pin on command.

[@CuriousMarc]

Exactly.

[@boonedockjourneyman7979]

Genius.

[@Kates-dead-goon]

Do I spy an electro boom moment at the end of the video? Pretty sure I saw some of the patented Lucas electrical system magic smoke escaping……

[@Victor-vc9br]

Awesome!

[@srfrg9707]

Holy smoke!

[@nbtmx1]

For ultimate sacrilege replace the processor with a fpga

[@waynestock300]

Ahh, the magic smoke..