today I got to talk to Bill Mensch, one of the designers of the iconic 6502 microprocessor, and show him the Monster 6502. he's holding a blank Monster 6502 circuit board I gave him.
we had a lot to talk about, as you might imagine!
one of the things we discussed was the design process of the 6502. a critical part of the planning was a flowchart that showed how every instruction was executed. everything else was derived from this.
the schematic looks more like a blueprint and it's about the size of your kitchen table. it's arranged just like the chip layout.
this type of schematic drives the layout, so the approximate routing and placement is already completed.
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i printed a new panel insert that has two BNC sockets on it (the original probes would have had captive cables)
the tricky part is that this oscilloscope has a 333K ohm input impedance instead of 1M like umm every other scope on the planet. fortunately someone designed a little conversion circuit...
in honor of Sim Wong Hoo, here's a quick historical review of the Sound Blaster! 🧵
but first we have to go back to their first sound card, the Creative Music System from 1987. (image credit: Bratgoul on Wikipedia)
this card has some special "CMS-301" chips. if you peel back the sticker, they have had their top marks removed. they're actually SAA1099 synthesizer chips made by Philips. Creative wrote music composition software for musicians on the PC.