See Chapter 1 over at: https://hackaday.io/page/2303-40107

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When I first signed up for this account I was like "oh yeah! I'm a pretty cool part-number!" And then I realized the part-number I thought I was was actually the 40106.

The other day I stumbled upon another 40107:

This guy was sitting in my "unsorted ICs" bin, which mostly came from old motherboards, etc.

(I was sorting through it trying to find cool uCs/CPUs to use for the 1k Challenge).

But, this guy... This guy... Oh man, I remember this guy!

How cool is it that it has my user-number?!

'Cause, when I was 15, I built an LCD controller... The biggest TTL project I'd ever attempted, and amongst my first microcontroller projects:

https://sites.google.com/site/geekattempts/old-projects

And a HUGE part of designing that circuit was reverse-engineering that friggin' LCD display... for which there was basically no data, and despite having somewhat standard row/col drivers (whose datasheets took *weeks* to locate in the early-internet-era), those were driven by an unknown programmable-logic device.

So, some guy was awesome enough to respond to a forum-post with a schematic of the motherboard this was originally connected to (where he got it? Boggles my mind):

From this I was able to figure out the missing pieces regarding what to feed that PLD, and obviously, the much-needed pinout (nevermind contrast, -20V, etc.).

So, obviously, this image is somewhat-deeply ingrained in my brain... And stumbling upon that 40107 chip marked "AMSTRAD", this image popped into my head... and I was like "Whoa, this is the character-set ROM for my LCD project!"

.... yeah... no. That's the 40109.

But it was a pretty cool moment, anyhow. And pretty funny, looking back on it. And even funnier when you consider I did similar with the 40106 CMOS chip.

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So I did some searching, and it turns out the 40107 is a BIOS ROM, I think, from that same machine... One of two (for the 16-bit bus?).

And a little bit more searching resulted in a page where someone had listed all the ROM chips used in Amstrad computers, and another page where these ROMs are actually referenced in the source-code in a project on Github... Weird? (Emulator?)

It's pretty wild how much info is out there...

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The machine these came from... that's another story, but let's just say the Amstrad PPC640 was a pretty groovy "portable" (read: luggable all-in-one) PC-compatible that I used to carry around with me, coding in Basic, and playing old games, even during the early Pentium era:

And I feel a bit ridiculous for having taken *two* of them apart (who gave me these, anyhow?! And did I really have *two* at one point?! I definitely have two *screens*. Weird.)

...

Ahhh the ridiculous rabbit-holes...

Anyways, I suppose I might try to think of something to do with that 40107 to go along with my other 40107's (I think I ordered two)... So now I've got a ROM and some NANDs... 'spose I *could* use that ROM's randomish-data as something like a "character-generator" or "sprites"... or...?