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Loopy Byteloose
07-13-2006, 05:23 PM
This has long been a back-burner project of mine as you can have tens of nodes share the same wire.· Each one can have a BasicStamp, or a SX-Parallax chip, or a Propeller working with other distant nodes.· Two or more groups can broadcast and recieve independently as there are over a half billion addresses available [29bit addresses].

To that end.
1. I have created a schematic and board based on other designs and intended to maximize what can be done with the CANbus Controller as a hacker and a hobbyist.· [These are EAGLE files]· It is a small board that can be used with a breadboard or become part of a permanent installation inside something as small as a conventional electrical outlet box.

2. I have created a Color-Coded mapping of the Registers [the SRAM] so that programing via SPI becomes easier, faster, and more obvious. [This is an EXCEL file]· This document has really helped me to grasp programing the MCP with the BS2p.· I am now working on a test bench model and hope to have a tutorial later this year.

For some reason unknown, I cannot directly UPLOAD these files for your review, but they are available to anyone interested.· Additionally. I am considering a production run of about 25 boards [about 2"x3"] to provide them at a minimal cost; say $5USD without parts.··

CANbus really isn't needed in point-to-point communictions unless you require CRC [Cyclical Redundancy Check], but it is sure nice when you want a dozen nodes for a complete Home Automation set up that is independent of the Internet [no viruses and no hacking into from the outside].

Also, there are hackers that work with the automotive applications to modify and customize modern car performance.



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"If you want more fiber, eat the package.· Not enough?· Eat the manual."········


···················· Tropical regards,····· G. Herzog [·黃鶴 ]·in Taiwan


Post Edited (Kramer) : 7/13/2006 9:27:12 AM GMT

Bamse
07-14-2006, 11:01 AM
Kramer,

This is still on my back burner, but it sounds really interesting...

For $5 I commit to one board without the parts, no problem...
How about shipping, can it be kept·around $5 as well ???
Just one catch, I cannot do Surface Mount, it has to be through holes for me...

It might take a while before I get to it, but if it helps you get started with the boards, I'll buy one from you now...

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Living on the planet Earth might be expensive but it includes a free trip around the sun every year...

Experience level:
[ ] Let's connect the motor to pin 1, it's a 6V motor so it should be fine.
[ ] OK, I got my resistors hooked up with the LEDs.
[X] I got the Motor hooked up with the H-bridge and the 555 is supplying the PWM.
[ ] Now, if I can only program the BOE-BOT to interface with he Flux Capacitor.
[ ] I dream in SX28 assembler...

/Bamse

Loopy Byteloose
07-14-2006, 03:31 PM
A board without parts is merely postage. Since I am in Taiwan, it is about $2USD to anywhere in the world. I am an English Teacher, not an electronics business. So, I really don't want inventories and other headaches.

I am looking at setting up a Yahoo Web Site for this and whatever. At this time, I need people to send me a PM with their web address if they want to look at the artwork [I will respond by forwarding the three files.

At $5 each, you still need at least TWO boards to communicate. About $12USD total. You would provide the 7805, the MCP2515 and the MCP2551. Other parts are somewhat trivial as I have left interfacing to 0.1 headers and jumpers. Nothing that is hard to get.

The file on Register Management is in COLOR and meant to help you read all the abbreviated names with greater ease. It certain works for me.

It is also intended to guide you through intialization of all the 128 registers in any fashion you care to design. If you want to wait, the really proof of feasibility will be when I have my PBasic Code complete for a Master Node.

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"If you want more fiber, eat the package.· Not enough?· Eat the manual."········


···················· Tropical regards,····· G. Herzog [·黃鶴 ]·in Taiwan