Re:Wristwatch microchip with only discrete semiconductors
by unwind on Monday February 09, 2015 @05:45AM
(#9020540)
A bit annoying that this piece repeats the fundamental mystery of the design:
The device runs off of a 12 volt DC adapter, and the clock’s timing is cleverly inferred from the US standard of running electricity at 60 cycles per second.
Of course, one major characteristic of DC is that it has no "cycles per second", so the above makes absolutely no sense. If the clock is fed by a standard (external) DC supply, it doesn't have access to the cycles of the main power so it can't rely on those.
I would have hoped that someone writing for Make would react when writing that, and actually do some journalism and dig up how it really works.
Re:Wristwatch microchip with only discrete semiconductors
by Sanddancer on Monday February 09, 2015 @02:22AM
(#9020054)
Yah, one of the mods may wanna change the title. This is made with discrete semiconductors, but is not just diodes and resistors as there are a bunch of mps6531 and other transistors in this.
Re:Wristwatch microchip with only discrete semiconductors
by mostly_harmless on Monday February 09, 2015 @02:08AM
(#9020028)
I imagine this was designed at a higher level, then exploded to smaller parts. For example, usually a 7-segment display controller is used to translate an input value to one usable by the display, but it looks like he soldered one up manually.
Similar to inlining functions in software, but all done manually in hardware.
https://news.ycombinator.com/item?id=8934474
The device runs off of a 12 volt DC adapter, and the clock’s timing is cleverly inferred from the US standard of running electricity at 60 cycles per second.
Of course, one major characteristic of DC is that it has no "cycles per second", so the above makes absolutely no sense. If the clock is fed by a standard (external) DC supply, it doesn't have access to the cycles of the main power so it can't rely on those.
I would have hoped that someone writing for Make would react when writing that, and actually do some journalism and dig up how it really works.
Similar to inlining functions in software, but all done manually in hardware.