Micro Basics

In a recent piclist message Jinx mentioned two methods he uses to drive static LCDs, and sent me the following to share. Click on the images for larger versions.

The 16F628 circuit is an up/down timer/clock, with optional dome bell or piezo bomb as the alarm

The two weak pull-ups on the ICM7211 data lines can be put in circuit by the user with jumpers, and those lines are read as '0' or '1' by the PIC, which then enables s/w routines if necessary.

Setting the display is simple - sequentially select digits with the 4017 and the 4-bit data on the data lines appears.

My experiments with backlighting.

I recently saw a cute little, inexpensive GPS module offered at Digikey that includes dual PCB antennas (I assume, maybe it's one large antenna?). The company offering it, Antenova, focuses on antennas, in particular PCB antennas, and I expect this module mainly showcases their technology.

----------

Please support this site: If you find this information useful, interesting, or entertaining, please help me by voting for my entry on the MyPIC32 contest, and learn more about Microchip's new line of 32 bit microcontrollers. By viewing a few of the contest entries each week you will be eligible for community prizes, such as an iPod Touch. Thanks!

I heard about The Great Internet Migratory Box of Electronic Junk from a Hack-A-Day article, and put my name on the wiki as desiring to receive one. TGIMBOEJ is best explained as follows (from http://tgimboej.org/ ):
----------
The Great Internet Migratory Box Of Electronics Junk is a progressive lending library of electronic components. An internet meme in physical form halfway between P2P zip-archive sharing and a flea market. It arrives full of wonderful (and possibly useless) components, but you will surely find some treasures to keep. You will be inspired look through your own piles, such as they are, and find more mysterious components that clearly need to be donated to the box before it is passed on again.

I participated in NaNoWriMo 2006 - the National Novel Writing Month, and successfully wrote a 50,000+ word novel - Field.

The first dozen or so pages start with a couple sent into orbit dealing with isolation, then flashes back to the middle of the problem that sent them up there in the first place.

I enjoyed writing it, and you'll find it quite enjoyable if you enjoy a bit of science fiction, set in our time.

You can get all 220 pages as a download or book for a very reasonable price.

Click here to buy the book or PDF

Click here to read the beginning sample

I had a Radio Shack 300-in-one electronics kit with the little spring contacts and wires. I’ve been interested in seeing how snap circuits (which have been around for quite some time now) worked in real life, but figured they’d disappear sooner or later along with all the other electronics that’s disappearing.

Back when you didn’t have a computer in every house, and tapes were still cool it was neat for kids to design a “big ear” amplifier, or a buzzer that turned on when the lights went out.

...

A Bed of Nails tester is an array of spring loaded pins (pogo pins) that accept a circuit board. The circuit board is pressed down onto the pins, and each pin makes contact with a given pad or contact on the PCB. The other side of the pin connects to circuitry used to test the PCB.

Bed of nails testers are used in PCB fabrication to make sure all the traces and vias are complete, as well as PCB assembly to test proper operation of the circuit, and may also be used to program FLASH, EEPROMs, microcontrollers, and other parts after assembly.

Phil Eisermann responded to a recent inquiry on the PICList on constructing a bed of nails tester:

Alex Harford posted a message on the piclist (electronics enthusiasts, mainly PICmicro microcontrollers) debunking the common belief that if a person in the USA digs straight through the center of the earth, they'll end up in China.

I determined to resolve the question and explore where the end of the tunnel occurs given any spot on earth. I spent an hour making an antipodal geography tool using Google Maps to answer the question:

Of the various delicious foods my Grandmother (maternal) made, a few stand out to me. This is how she would season oyster crackers:

Ingredients:

• 24oz of oyster crackers
• 1 Cup Oil
• 1 package Hiden Valley Ranch Homestyle Onion Dressing
• 1/2 teaspoon garlic powder
• 1/2 teaspoon dillweed

Instructions:
Mix everything EXCEPT the crackers.
Add the crackers and mix really well.
Spread out on a cookie sheet.
Bake at ~300F-325F until crispy.

Perhaps I will locate and add the recipes for spiced peach jam, Alcapulco Delight, and her coffee cake...

Generally, there are two main timepieces made for the blind. There are Braille watches which usually have a flip-up cover over a regular analog watch face. By feeling the position of the hands on the watch one may determine the time. The second is the talking watch. A button is pressed whereupon the watch announces the time.

It occurred to me that one could easily make a third type which would instead vibrate a series of pulses that provide the time, perhaps in a more discreet manner than the prior two methods. I knew that I wouldn't be the first to think of it, so I did a search and found only one product which uses this method.

Most projects need to output information to people. Many projects use text LCD displays, which are very flexible and can provide a lot of readable information.

But many projects need to display only a little information. Maybe they need to be even cheaper. Perhaps there's only a small battery available and it needs to run for a long time. In these cases a statically driven LCD display or panel may be all that's needed.