|
ok, but what about this loop here, can i do that, having multiple a/d conversion on one chip ?
loop:
ADCON0 = %10000001 ' Configure and turn on A/D Module
ADCIN porta.0, input1
pause 50
ADCON0 = %10001001 ' Configure and turn on A/D Module
ADCIN porta.1, input2
pause 50
From the definition of ADCON0, I can only choose one pin for A/D conversion. Maybe thats why it get mixed up .
Last edited by lerameur; - 3rd January 2007 at 20:39.
|
You can do A/D on more than one pin, just not at the same time. I'm not sure why it didn't work for you in the one post. Maybe not waiting long enough between conversions and/or long enough between switching A/D channel assignment. I think you have to wait awhile, not only after the last conversion, but after you switch the channel, which ADCIN does for you. So, again, not sure. I'll think on it. Until then, double check your configuration, TRIS assignments, ADCON setup, etc.etc.Originally Posted by lerameur
And you shouldn't have to use more than one channel for your project, unless I missed something there too...
|
HI,
I dont have to use more then one for this project, But I had this problem before and did not persue into it, so I asked the question just on the way. I read on a site, just like you said, adding a capacitor to the output of the sensor or battery will help. The thing I dont know why it works, I tried these two program they both works, just dont know why the program with just one ADCON0 works
Two Adcon
ADCON0 = %10000001 ' Configure and turn on A/D Module
ADCIN porta.0, input1
pause 50
ADCON0 = %10001001 ' Configure and turn on A/D Module
ADCIN porta.1, input2
pause 50
One ADCON0
ADCON0 = %10000001 ' Configure and turn on A/D Module
ADCIN porta.0, input1
ADCIN porta.1, input2
pause 50
See they both work, but I did not configure port A.1.. why ?
|
You're using the ADCIN command. Ya think maybe PBP sets it up for ya?
I know the PBP manual doesn't explicitly say it that it sets it up for you, but it does say that ADCIN reads the 'channel' and also says all you have to do is set the required pins to inputs, it doesn't really say to select the channel you want to sample... I suppose the manual could be a little more informative in this respect.
I just looked at the ADC section of the 'F88. It's a bit different than some of the other PICs. Not only do you have to TRIS the pins you want to inputs, but you also have to enable the A/D in the ANSEL register. I don't know if PBP does this for you or not.
You can easily check for that in your .lst file after compiling the program. Just put a comment around the line you're wanting to check and search for that comment in the .lst file. Should make it a bit easier for ya...
|
hi,
Ok I got the A/D working now.
I bought another RF module kit from this web site:
http://www.robotshop.ca/home/product...ity-tx-rx.html
( actuallyI just had to drive there).
I use the exact program and configuraiton and I am getting contact output on the lcd :
TempC : 0
TempF: 32
here is what I see on the scope:
http://www3.sympatico.ca/lerameur/
Last edited by lerameur; - 4th January 2007 at 17:27.
|
A/D is working as expected? Values are what you need and all that?
RF Modules - sounds like you should take them back and get another pair of the same thing you've already got.
|
I bought three pair of them , They all act the same...
it looks ok from the scope doesn't it ??
A/D is working as expected? Values are what you need and all that?
Yes
Last edited by lerameur; - 4th January 2007 at 17:49.
Members who have read this thread : 0You do not have permission to view the list of names.
Posting Permissions
Bookmarks