@tubetime have you ever seen a moon? You will. And the company that will bring it to you? AT&T

@tubetime

Società Generale Semiconduttori

https://it.wikipedia.org/wiki/Societ%C3%A0_Generale_Semiconduttori

Now that is a great name for a chip company.

@tubetime https://www.inc.com/magazine/19851101/8957.html

@tubetime I swear to $deity some of these chip manufacturer names read like white label Chinese sellers on Amazon. XD

@tubetime "Please don't use if you're allergic to Zytrex or one of its ingredients. Please reach out to your physician if you have questions, and remember to use logic gates responsibly."

@tubetime "Quality Semiconductor", now owned by IDT.

@tubetime I just searched the first line on DuckDuckGo and came up with Quality Semi, specifically a 1-of-8 decoder, by the looks of it? Digikey seems to have a similar product in SOIC-8

https://www.digikey.com/en/products/detail/rochester-electronics-llc/QS74FCT138CTSO/10499614

I wonder if this is the same Quality Semiconductor. too bad about the quality of the chip marking

@tubetime Might be SEMI PROCESSES, INC. https://opencorporates.com/companies/us_ca/0827527

@tubetime could be this one https://www.spisemicon.com/category/about/spi-semicon-north-america/

@tubetime

Semi Processes Inc.

https://www.questcomp.com/part/4/sp74hc113n/384845007

At this page there is also a data sheet.

@tubetime Sescosem

@tubetime
Sescosem

Sescosem was formed during the merger of Thomson-Brandt and CSF in 1968. Thomson's SESCO division was merged with CSF's COSEM division to form SESCOSEM. Sescosem's products were never a big commercial success, but the technology was eventually absorbed in the subsequent mergers that created STMicroelectronics.

https://how-to.fandom.com/wiki/How_to_identify_integrated_circuit_(chip)_manufacturers_by_their_logos/P-T

@tubetime I have a bunch of these in my parts bin they are quite common in the Netherlands (Europe).

Probably don't exist anymore as I have only ever seen 74LS never any CMOS variants.

this little guy turns the 8-bit value into hex! it's also configurable: you can flip the digits upside down for when you plug it into the left side of your breadboard. it can also trigger and latch data on the rising or falling edge of the optional trigger pulse, it can be level or edge sensitive, and you can set it to "single shot" capture a single value.

@tubetime hm. Which palette is that? Some trickery?

@tubetime 🥺

@tubetime Thats neat, kudos for you and your brother!

@tubetime

@tubetime This is just subtle enough to make you double check your math and make sure you have it oriented in the correct polarity.

Unless it's a bit too subtle and then you f#@k around and find out how much energy is in that misapplied capacitor.

We used to say "just put a BFC across the output of that lumpy 48v full wave rectified transformer and you'll be fine"

@tubetime being an electronics apprentice in the 1980s was sometimes a Trial By Fire. Charging a big High Voltage electrolytic cap, wrapping its leads around it and tossing it to the apprentice was a thing. Ow-diddly-ow. Then connecting a tantalum cap backwards across the output of a DC supply and switching it on just as the apprentice walks up… Good Times?

@tubetime holy crap, is all of this so that it can support an essentially infinite/full duty cycle? I mean I’ve lugged 4160V cables and they don’t need this (I mean, yes, they’re AC and high voltage specifically to reduce current and the resultant heat from I-squared R losses, but still)

@tubetime as an EV driver, this is super cool to see!

ouch.

in my own libraries, i like to use multiple markings for pin 1. here i have a semicircle at one end of the chip along with a circle right next to pin 1.

@tubetime Long overdue. I had no idea they were following a standard, its a terrible standard. I've reversed SWD connections a half dozen times because a coworker decided to orient the connector unintuitively and made no attempt to augment the default terrible pin one marker.

@tubetime yea, I have an issue with this too...

the machine is very non-descript and often mistaken for a PC, but it is not.

@tubetime who's locking them down? I've generally not had any issues grabbing the vendor STEP models and using them in KiCad...

@tubetime "locked down" how? /genq

@tubetime ? what software?

the scan was a little tricky to stitch together since the board is longer than my scanner 😅

@tubetime EGA board?

@tubetime some kind of ISA card?

@tubetime still not as cursed as DB-23.

@tubetime it's simply adorable

@tubetime Shouldn't that be DS-15 for single-line of pins?

@tubetime You can just drag a line through all the capacitors. Watching that copy/paste operation w as painful :-)

the results: https://github.com/schlae/EGAMemory

@tubetime This means I shouldn't use them as a serving dish! Y'know, because the big spindle hole isn't enough deterrent :)

@tubetime Ok I'm pretty stupid so ELI5: What does that mean, is this PFPE oil dangerous? I've built little decorations out of old disk platters, was it stupid to hang them inside my apartment?

@tubetime make shure to not loose alignment of the platters or else you gotta need to deep-reformat that thing!

@tubetime I love it! My very first homemade computer (25..30 years ago now) was wired up on a breadboard very much like that, and even now there's still plenty of magic watching yours come to life. Nice job!

@tubetime from the description on https://www.cpu-world.com/CPUs/PACE/index.html it sounds like a nice architecture but unfortunately very slow.

@tubetime AFAIK NSC only called the original PMOS version PACE, and always referred to the NMOS version by the INS8900 part number.
Oddly enough, the NMOS version had the same timing specifications, rather than being faster than PMOS.
Years ago I discovered that the commonly found scans of PACE fig-forth were missing a page, and also had another serious bug. My corrections are on Bitsavers. The author of PACE fig-forth said that as far as he knew, no one else had ever used it.

@tubetime
Is it hot on the bezels?
Could be:
1.- Heat from the fluorescent lamp that makes the liquid crystals to change the polarization of the light in the wrong way.
2.- Heat increasing the effect of the already de-laminating screen (does fix itself if you press the bezel?)

@tubetime Mac people call this tunnel vision. Seems to be from moisture ingress. Baking the panel - or leaving in the Cali sun on a dry day - might help.

@tubetime Hi, it‘s maybe a loose connection of one of the LCD bias voltages. As there is only minimal current flow, the Panel charges up with time?