MCP3202 only 10bit?

Comments

• Peter Jakacki Posts: 10,193

  2016-05-01 12:39

  Which object? Always best to provide a link to the one you are using or post the code.
• kwinn Posts: 8,697

  2016-05-01 13:55

  guenthert wrote: »

  I'm using the MCP3202 object from OBEX to read the values from a MCP3202. I find that the lowest two bits are always zero, making it effectively a 10bit ADC. I couldn't see an obvious problem with the software, so I wonder if my chip is broken or I got a fake? Anyone made similar experiences?

  
  It's definitely a 12 bit 2 channel adc, and I have used it a couple of times before standardizing on the 3208. IIRC I used the MCP320x_ez driver.
• guenthert Posts: 36

  2016-05-01 19:42

  > Which object? Always best to provide a link to the one you are using or post the code.
  Right you are. It was just that I downloaded the code a while ago and only recently took this 'project' up again. I just had another look and am able to identify it as http://obex.parallax.com/object/386 . I now see a comment there indicating that it might not work. Hmmh.
  
  Googling, I also found https://github.com/mrmorphic/led-cylinder/blob/master/code/lib/MCP3202.spin , but that looks like it needs more work.
  
  Now I have a few more links I need to digest, but first I need to get lunch ...
• guenthert Posts: 36

  2016-05-01 19:48

  kwinn wrote: »

  [..] IIRC I used the MCP320x_ez driver.

  I couldn't find that. I wonder if it got lost (like Pavel's object, see http://forums.parallax.com/discussion/115291/mcp3202-12-bit-adc-converter-c-code-posted-in-obex).
  
• guenthert Posts: 36

  2016-05-01 21:20

  Ok, I tried the MCP3202 reader in SPIN (http://obex.parallax.com/object/78) and after some massaging (I don't have an LCD and I intend to use one pin for data in- and output), I got that to work. The chip is fine, all 12bits of it.
  
  This was just a test more or less to satisfy my curiosity, but eventually, I'll have to look more closely, what's wrong with the PASM driver (wonder, whether it might be timing).
• kwinn Posts: 8,697

  2016-05-01 22:54

  Sorry about that, I was referring to this one "http://obex.parallax.com/object/315" in my earlier post.
  
  Now using "http://obex.parallax.com/object/371" since settling on the MCP3208. Not much point in stocking multiple adc's since they are only a few cents apart in price.
• guenthert Posts: 36

  2016-05-02 00:29

  Thanks. Turns out (as you have already guessed, I'm sure) I had a silly bug in my code: I imported the MCP3208 driver object and didn't notice that, as I called the object MCP3202 <facepalm>