i haven't done a cross section in a while! here's one of a kernel of corn. i found it at the bottom of a bag of popcorn.
and here's the annotated cross section of the kernel of popping corn. this one didn't pop so i cut it in half.
ok here is the *real* annotation. i'm no botanist so there's probably cool stuff i left out.
also am i totally nuts for complaining about the shell/pericarp of popcorn that always gets stuck between my teeth, or between a tooth and the gum? please tell me this happens to the rest of you too 🍿
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digging through the IBM BIOS for the PS/2 Model 77, i found this interesting bit of code that tests if it is running on a 16-bit 8086/8088 or a 32-bit 286+.
while running in real mode, the BIOS tries to execute the MOV EAX,0xffaa0055 instruction. even though EAX is a 32-bit register, this is possible to run in real mode using the segment override prefix, which in this case is the 0x66 byte.
unless of course you happen to be running on a 16-bit 8088/8086, in which case the 0x66 op code aliases to the 0x76 op code, which is JBE (jump if below or equal). since a previous instruction left the zero flag set, it branches to the target.
so an early 6502 microprocessor has been imaged! the first versions from 1976 lacked a ROR (rotate right) instruction, so let's dig in and see what changed. 🧵
they look very similar at first glance. on the left is the 1976 revision A, and on the right is a later revision D (mfg by Rockwell, in this case).
here they are, imported into GIMP, and roughly overlaid. there are a few pads that have been moved around (mostly on the left) and the pad structures have changed.
ever wonder where these lone traffic cones come from? out of place; out of context, often with a stencil that doesn't match your city's public works department? 🧵
this cone has a buddy. they're different, but they perform the same function. who or what is TBC anyway?
despite the fact that most people treat traffic cones as shared property, they very much have owners!
some projects start with a breadboard--others start with a bare wooden plinth.
this one is a bit quick and dirty, so the parts (at least for this version) are 3d printed in a hurry.
here's a quick test fit. the two coil forms at the bottom turned out pretty nice, but i think i'll redo the other parts. brass would be a good look, i think.