Nothing wrong with that at all except never accept that one design is always the best route to take
I dont have any problem with what you do or anyone else but id like to see you progress not regress
So its right that you should ask many questions I would be and always do
For example to make you think further where will the 74hct595 be in possibley a years time
If I was to build this would I be able to get replacement parts? What about my customers? Will I be able to provide a years warrenty based on this current design? Aaaaah thinking now
So let give you another example
What year are we in now 2013? Yes close
So what has superceded the above chipset bit like a pc you dont keep old pcs to perform tasks of the modern day
Yes its true to say put them to good use good for starting people on that path of study Thats not a bad idea thats a sensible attitude
How ever bussiness wise would this be sensible considering modern day needs in conjunction with software and internet related technology? ,hmmm Good question?
Lets see when do you think this circuit was published?
This is going to be of a shock to you so Im going to give you the answer here of 2006 that means to all intensive puposes its now obsolete, however its a better design and you would still be able to get parts or should I say change parts for equivalents fairly easily without having to do away with too much
The structure would remain the same as too the principles of your current design Nothing wrong with that idea, but what is it that you should extract
Shift registers? Yes
3to 8 line decoders? Yes
What about the serial port I think they should still hang onto the 9way d type and also the parrallel port its still very usefull, but, how many printers these days have a centronix port or parrellel port or serial port 9way dtype
What else is rs232 synchronous or asynchronous now and what about the processor itself New versions of pic incorperate usb module example the 18F range and synchronous, asynchronous ports with more general purpose registers and a tx, rx buffer with error indication registers Rx, Tx buffer overflow flags and these days also I2C bus modules making coding not simpler possibly in one context but smaller in another context so less instruction time better throughput and error checking in general
Important if you are dealing with Networks
So what happens to the 3 to 8line decoder? We. write software for a pic cpu instead and scrap that chip or, we upgrade the processor to incorperate not only shift registers which we program into the chip we also include that part of the current schematic into one single chip plus usb ready so that we have up to date technology and improved overall memory plus throughput making this compatible with modern day pc laptop etc
Have a look because this is where you learn fast
What else is available and free for download Try the amicus18 compiler from www.crownhill.co.uk Its free doesent cost you a penny and its what mussa Usb ready
Now go and download the compiler and look at the commands they offer Simpler, easier,gets you to grips faster Rad " RAPID APPLICATION DEVELOPEMENT "ready can use easily, programmer built in, is compliant with most modern day applications
What could it do with Can bus functionality thats about it for today Hope you enjoyed reading my comments Not meant to offend but to educate Big difference
