Hi all
how can i interface DS1820 temperature sensor with 89s52 uC. So that it can display temp on LCD.
thanks in advance
aditya
I think there's some teaching going on but, apparently, not much learning...
:-(
"not as good as the datasheet, I have seen much 'untested' 'manufacturers code'"
The manufacturers "official" code is probably written by some application engineer somewhere. Possibly quite bright, and possibly quite good with the hardware. But very seldom a good programmer.
Much of the "official" manfuacturers code is way worse than the code you can pick up using Google. I prefer to look at popular code before looking at "official" code.
I might do a quick scan through the code just to see if it shows any signs of big surprises - things I failed to pick up from the datasheet. But I'm normally extremely sceptical to using manufacturers code in release projects.
Coding from a datasheet means that I know the reason for every single source line. A lot of manufacturers code has strange lines that can't really be explained. Possibly left-overs from ports from other chip variants. Possibly left-overs from trying to get the code to work. Possibly absolutely vital lines. But I have no way of knowing.
If I code from the datasheet and it works, then there is a reasonable chance that I did a good job. If I find that the datasheet does not have enough information for me to implement the function, then it is time to rethink the chip choice.
In the end, downloading code is a question of trust. And a question of looking at the code and make educated assessments. And to check feedback and other relevant information. And the knowledge that I can understand and maintain the code take care of any problems. But I have had way better experience with non-official code than I have had with manufacturer-supplied releases. I'm not talking about Maxim (Dallas) now but in the general case.
Keil, ST and others provide their own flavor of firmware USB support for various chips. Now that is a big piece of software, quite heavy too (in terms of runtime cost, ROM etc.). Personally I prefer ST's implementation over Keil's, but since most people don't know all the details about the exact functioning of the USB protocol (indeed, a complex machine), they tend to trust anything that seems to work. At the same time, there are a couple of open source (hence: written by hobbyists) implementations out there, and I have to say - they don't look bad at all (but I haven't tried them yet).
Open source != written by hobbyists.
Some open source projects are hosted and run by commercial companies, or derived from commercial projects to promote a technology (or sneak away from the support costs).
A lot of open sources are written by professionals who also happens to burn for a course or feels that a cancelled project should not have to die in a quick "rm -rf".
And some open sources are written by (often very gifted) amateurs.
And then we have the students who feels that their hard efforts are true master pieces to be saved for the following generations to admire. If the download links are flashing and twirling, it may be a sign that the bandwidth should be saved for another download, another day :)
You're absolutely right, of course...I guess I was projecting my personal condition: My day job is embedded-related, but I am also a hobbyists at the same time...
Some open source projects are hosted and run by commercial companies, or derived from commercial projects to promote a technology (or sneak away from the support costs). I know of many such cases for the PC (and a few other thingies) but NONE for the '51 (or for that matter, any small embedded)
Erik