
The hard way to recover the IBM 5100 Non-executable ROS - classichasclass
https://github.com/stepleton/5100NonExecutableROSDecode/blob/master/WRITEUP.md
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jandrese
Seems like he made a lot more work for himself by trying to save a bit of
space on the original capture and doing it at low resolution and with an
unsynchronized v-blank.

I did something similar to this many years ago from a screen recording using a
copy of gocr and netPBM. Cutting out blocks of text using netPBM tools and
feeding them into gocr ended up working out quite well and didn't take
enormous amount of cpu training some ML model.

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ncmncm
I think masochism has to figure strongly here.

Otherwise he would have re-shot at higher resolution and more frames per
screenful. Or something. One goal was to get the bytes out, but the other goal
was to achieve it the hard way, and maybe learn some ML on the way.

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Dylan16807
At least reshot, even better write a small program to output each page in base
2/4 (with characters chosen for very easy distinguishing) plus a checksum.

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DanBC
I love this write up.

There is some information about the 5100, with lots of photos, here:
[https://www.oldcomputr.com/ibm-5100-1975/](https://www.oldcomputr.com/ibm-5100-1975/)

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jamesmp98
I love vintage computing and have wanted a 5100 for a few years now.
Unfortunately the only time I've ever seen one on sale was about a year or two
ago and I just couldn't afford it

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dev_tty01
Great write up. I loved the computation time estimates based on the target
hardware. I have designed a number of CMOS chips during the last 20 years and
I have always been amused that the 4 month fabrication time is quicker than
the time required to do full chip simulations, assuming they were even
possible. I like to refer to chip prototypes as custom real-time simulators.

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Darkphibre
That was an excellent read!

I'd be curious if he could have leveraged the CRC check as part of the
verification loop.

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bobblywobbles
You are much smarter than I, reading this article is evidence of that.

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vectorEQ
this write up gave me a headache just thinking about this task :D wow what a
battle to dump some bytes! excellent and interesting write up for sure! props!

