Printable View
I am looking into using a DS2480D and connecting a number of DS18S20s to it. I have the datasheet for both, but I seem to be overlooking the part covering the commands for the DS2480D.
Am I to still use the same OW commands or are there different ones for it?
Feels like my brain is disconnected from eyes. :o
Could someone stick my nose in the right place?
http://www.maxim-ic.com/appnotes.cfm/an_pk/192
A - I don't know why you would want to use a '2480 since PBP supports one-wire just fine, and even multiple 1820's can be easily done with a PIC, PBP, and maybe a single external latch, multiple ways of connecting multiple 1820's.Quote:
Originally Posted by manwolf
B - the command bits/bytes are listed in the app note, basically all over the place. There isn't a 'table of commands' in this instance. You have to piece it together.
Hi,
a look here ???
http://www.picbasic.co.uk/forum/show...42&postcount=7
Elektor link leads to a "C" written PC datalogging system via USB ( 18F2550) ...
Alain
Maybe I should switch to DS18B20 temp chips and set the addresses myself. There will not be a lot of pins laying around with what I have in mind.
I did find some code to query the bus to get the addresses but it uses a lot of space.
Thanks for the suggestions, I will keep them in mind as I flesh out the design.
Skimask - Thanks at least now I know I am not going crazy, I kept looking for the table but didn't find. Guess I need to print it out.
Acetronics - I found that post last night and it might be an option, but it uses a PIC18F2550. I am working with 16F chips although I might end up with 18Fs before it is over.
The ds18B20's are brilliant, and it's dead easy to address them from the pic all you need to find is the matching rom address for each device then talk to each one whenever you want :)
Seeing you're then using 1 wire anyway you can add any other devices you want to it like the ds2405 switch? all depends on what exactly you want to do with the temp once you've read it/set it
I followed Acetronics idea and it's dead simple, In my case I just built a small circuit and mounted it on the back of a 4 line lcd and using a usb lead JUST as the power supply and a TO-92 socket to plug the ds's into. then all you need is a small pic dedicated to reading the rom's (or reuse it afterwards for something else) and THIS(clicky) how to read the rom codes from 1 wire devices* and then this*(clicky) how to communicate with multiple 1 wire devices
The 1 wire commands threw me for a while, took a bit to get my head round them and I'm still learning (now about eeprom and timers)
Hi, Karen
You already had it in your computer !!!
EasyPic5 ... And MkBasic examples !!!
I just made a little Mod : skip the CRC ...
Demo Basic is enough to compile ...
Just compile ( with MkBasic ) and throw to easyPic5 ( PortE.2 in use for DS comms )
Alain ... Laughing !!!
OMG I cant believe I was so stupid as to not look there.
I actually got rid of the easypic it was too complex for a complete beginner like me, all i got it to do was learn how to drive the lcd display and ports but it did teach me something
I now have a pickit2 and icd2 although i dont need both, one was a free!
I'll run through that code later and convert it to picbasic pro shouldnt take too much doing. Thank you :)
Quote:
Originally Posted by karenhornby
Love the THIS(clicky) and your links, I had already found one, but not the other Thank you. :)
I would also like to say that it is not that we don't look, it is the fact that there are too many places to look. Examples might be included with one compiler, but not another. I have the EasyPic5, but didn't install MkBasic, went with PBP instead. Then I am reading here and see a post that an example is included with xyz, then I have to download and install xyz. My laptop has a very small drive and it is beginning to feel the strain! LOL
glad i could be of help to someone even if it's throwing an idea and a webpage, as I'm only a newbie and only started with pics a few months ago, learned how to use the lcd display with the easypic5 board then sold the board, not done anything with pics since, untill now when I'm starting on my curent project which actually involves learning about 1 wire commands, and I have to admit I foudn it totally confusing at first but I'm getting the hang of it now.
will help when I actually get the bits to build and test the circuit:) I prefer to sit here and work it all out and understand it first then try it and then I can find out where I've gone wrong.
Oh I'm using picbasic pro too, its brilliant :) I just couldnt get on with the mikroe basic at all
karenhornby
I purchased the LAB-X1 and then saw the easypic5 with the gLCD and wanted to plan something around it. SO far no luck, but this weekend a I am planning on breadboarding it.
I managed to get a single DS1820 working with the LCD, but everything I found with ow always skipped more than one device on the bus.
I even bought a number of books, one said it was not in the scope of the book and the other said they would cover it in a later chapter and then in the later chapter they refered you back to the first one.
I have been following your posts and seeing you making progress, good luck with your project.
I am wanting to have my app discover any device added to the bus without having to know the ID first, just one of those plug and play type of guys I guess.
SO I will share with you what I found.
I think it convert from PDS.
See link
http://www.picbasic.org/forum/showpo...68&postcount=2
.