I collect PLCs (programmable logic controllers) and microprocessor trainers. 

     I program microcontrollers for a hobby when I have time. They are like a computer on a chip with memory, I/O's (inputs - outputs) etc. even a built in R-C (resistor-capacitor) clock if you don't won't to use a crystal. Now I am moving up from the Microchip 16F84 to the Microchip 16F877 microcontroller with A/D (analog to digital) capabilities. Microchip in Arizona manufactures these chips which, according to most sources, have passed the production of Motorla line of microcontrollers sometime ago.

     It took a while to figure out how I was going to learn assembly language programming on my own. Almost all books start out stating no prior knowledge was needed and then proceed to contradict themselves. After researching and buying numerous expensive books, I lucked up on the Pictutor Course from Everyday Practical Electronics Magazine (EPE) which covered assembly language using the Microchip 16F84 microcontroller. The "F" means "flash" memory.

     One has to understand the architecture of a given microcontroller before using assembly language. Assembly language is much faster than the higher level languages but can be more difficult to learn.

     The Pictutor is produced by EPE in Great Britain along with their deluxe development board which has a LCD (liquid crystal dispay), a LED display (light emitting diode), 13 momentary switches connected to 13 LEDs, I/O ports etc. All one needs is an IBM (International Business Machines) or a clone, a parallel cable, the development board just mentioned and the accompaning free software tha comes with the couse and you're off and running.  Mr. John Becker really does a good job of getting the information across. And with his latest 3 articles covering the 16F877 microcontroller along with the other "inexpensive" development board kit and free software, one just needs the time to start!

     I collect vintage (1970's-1980's) microprocessor development boards and trainers with the 8-bit chips, Z80, 8080a and 8085. I have seven working MMD-1's (Mini Mico Designers by Elenco - see picture) including a listing of the monitor program and two nonworking MMD-2's which also have the 8080A microprocessors.

WANTED TO BUY OR SWAP THE FOLLOWING ITEMS

1) A 1702 eprom programmer.

2) A set of "The Family Home Computing Library Books" by Orbis Publishing published sometime in the late 70's or the early 80's. I have the first 5 books of the set. Not sure how many is in a complete set.

3) aa355 Labvolt manual or any info on how to begin programming the aa355 Labvolt.

If you have any of these or know someone that does, please email me at (Remove the Z for a valid address) zawa100@yahoo.com.

FOR SALE

1)  Brand new ACME 26 VDC, 30 amp linear power supplies

2) Working MMD-1s with manual containing the MMD-1 monitor program and other info.

3) Used  PLCs and Programmers - AB, TIs, Omron, Series One, Series Three, Series 90-30, Fanuc, GE, Sy/Max etc. Email me with what you are needing.