4 ms·
My story: my first real job after grad school was at Texas Instruments. It was a good job, and I enjoyed working there. A fellow new hire and I were tasked wit
by todd8 4y ago
My story: my first real job after grad school was at Texas Instruments. It was a good job, and I enjoyed working there.
A fellow new hire and I were tasked with fixing a machine that ran in a clean room where semiconductor wafers were made. On weekends while the line was down, we would go in, crank up one section of the line and let waste wafers travel through the line where very rarely they might get stuck in a multi-lane machine that would etch the wafers with some sort of acid.
The machine had over two dozen asynchronous motors, actuators, pumps, sensors and so forth. All generating interrupts and I/O events that were sent to a computer that ran the whole line and controlled all the machines.
We couldn’t slow down the machine, it had to run at full speed. The program controlling the machine was thousands of lines of assembly language—everything was assembly language, including the homemade OS that ran the computer running the line. It took like an hour for us to bring up the line and two more hours to see the machine do something strange.
The computer running all this had no user interface other than a some front panel switches and some panel lights that would reveal 16 bits of it’s 128K of memory at a time. This was in the 1970s before Ethernet had been invented.
It felt a bit like those escape room events where you know there is a solution, but you don’t know if you will ever get out. Without my coworker cracking jokes about our plight, I’m not sure we would have ever triumphed over that stupid machine.
- andromeduck 4y agoWhat ended up being the problem?
- genericone 4y agoThey ran the cycle again with one obscure parameter difference and it ran without issues until the Y2K bug took it down for good.
- porknubbins 4y agoTo jump on the bandwagon here- as a guy with zero hardware qualifications who likes to work on cars and motorcycles my first thought was a temperature issue. Not that I could’ve found the resistor issue, but this is not an obscure bug except maybe for pure software people.
- philliphaydon 4y agoI automatically thought temp too but only because of watching that aeroplane crash tv show which would go over a plane crash to figure out what went wrong. I remember one episode where they figured the wings would freeze and not move so the pilots lose control and would crash. They reengineered the part to not freeze during extreme temperatures.
- expensive_news 4y agoI did too, but the first line of the thread: “winter is coming (freezing emoji)” primes you to think about temperature. I’m not sure it would have been nearly as obvious if after a few months in the field I suddenly got a few bug reports. I think this might be a case of confirmation bias that people experienced when reading the article since the author tells you the solution in the first sentence.
- Ekaros 4y agoMakes me think that it could also be something more indirect like humidity. Temperature inside facility is likely controlled. But humidity might not or it might go to lower bound of what is desired.
- kabouseng 4y agoIn a clean room humidity is also controlled.