ZEPPP : Zero External Parts PIC Programmer

A couple of months ago I was asked if I could prepare a sort of workshop on one of my favorite topics: ASM Programming for PIC microcontrollers, which I of course accepted on the spot.  Now, I wanted to include a couple of “hands-on” lab sessions in this workshop, and because of this, I needed a way for all attendants to actually work with real PICs that hopefully did not involve purchasing PIC-programming hardware in bulk for what is probably going to be a one-shot activity.

The Quest

Simple DIY programming circuits exists, and in fact, my first PIC programmer was a home-built “Enhanced” NOPPP (No-Parts PIC Programmer); a fully functional device that required only a couple of components (Not really “No-parts” but pretty close to it). The problem is that it used the PC parallel port (R.I.P), and required an external power supply. And this goes for pretty much every “classic” DIY PIC programming circuit; they all either require extra hardware or can no longer be used on current computers.
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An update to my desk clock

I like to call this revision “Please believe me, I’m not a bomb”

Like a year ago I made myself a nice little desk clock that has worked fine since then. But recently I revisited the project to do certain improvements.

For starters I wanted a smaller board so I could fit it inside an enclosure.  I also wanted to power the clock from a rechargeable 18650 battery and add the charging circuitry to the design. I was also willing to give up with the ultra low power consumption and use a DC-DC booster that would of course draw more current but would ensure the clock gets a nice and stable 5V at all times. This has two advantages: It keeps a constant brightness for the display, and, more importantly, will give me reliable 5V in the aux port so I can easily interface the clock with other devices or external circuitry if I so desire. Read More