11/28/03 I hope everyone had a good Thanksgiving...Progress continues on the controller...so don't despair! All of the hardware planned for the controller is now breadboarded and functional except for the ORP interface. The ORP module has suffered a minor setback in that the probes are on backorder...but I am sure this will be resolved quickly. The X-10 interface is now complete and functional. The relay drivers have been laid out. The current controller will be able to control 5 direct relays and 16 X-10 outlets for a nice total of 21 devices that can be controlled based on time,date,pH,ORP,Tank Temp, Room temp, and Float levels. I believe that is a major plus to this controller. The main things that will be focused on now are the coding of the interface on the controller, and the PC software for the controller...don't worry the plan is to make the unit completely functional without ever connecting it to a computer. The project is quickly outgrowing even the Atmega32 chip we had hoped on squeezing into. I will show you our solution to this in a bit...First a shot of the breadboard to date:
Well, It is huge on the breadboard, but the final layout will be small and modular. Next a quick shot of the X10 module. The way X-10 works in terms of programming is that in order to use the X-10 protocol in the program without fears of liscensing issues, the TW523 interface must be used. This is inexpensive, approximately $20, and is of course optional..but very nice for easily controlling things.
And you may have noticed an ugly ratsnest of grey cable on the breadboard...well this is "growing pains". It is the breadboard interface for the Atmega128..the flagship for now of the Atmel microcontrollers. You will see in the next picture that the entire chip is very small, less than an inch square and is packaged as a TQFP64...which means tough soldering. I made an adapter for the chip, and the adapter is planned for the final board, so it uses 4x16 0.1" headers arranged in a square, this will work well when building a pcb, but does not work at all on a breadboard...hence the cable mess...but it works, and we will likely be moving to this chip at somepoint in the future. The plans are to provide the DIYers out there premounted Atmega128s on the adapter so you won't have to do surface mount soldering, or you can always download the adapter file, etch the board and do it yourself...once I get those files up :).
