​ ​ ​ ​ 16x2 LCD showing two lines of Boxes - Page 3
Page 3 of 3 FirstFirst 1 2 3
Results 21 to 23 of 23

Thread: 16x2 LCD showing two lines of Boxes

  1. #21
    Senior Member
    Join Date
    Jan 1970
    Location
    NSW Australia
    Posts
    356

    Default

    Quote Originally Posted by ojd233 View Post
    I checked this with a 10K resistor but still no change. When you said it is the same as the download layout, I tried a 22k(that's what I am using from download socket to the 20m2) to see if that did anything, but still not working.
    Actually, I don't recall having said exactly that, but, as Hippy pointed out the 10k pulldown resistor needs to be on the PICaxe side of the 1k inline resistor. So technically speaking the resistor layout is the same as the download circuit, but the values are not. I would NOT suggest using a 22k resistor between the two ICs as it's too high in value. You really need to try the 10k to ground (on the PICaxe side of the 1k resistor) and leave the 1k between the ICs as per Hippy's example. Did you try that? If so, then as Hippy pointed out, to help further, the folks here are going to need some decent photos of the top and bottom of your PCB to see if we can spot any additional issues. The fault could be anywhere.

    A really good place to start is, with the power off/disconnected, put your multimeter into a low ohm range, connect one multimeter probe to the input ground (negative) connection, and then use the other probe to check ALL of the component pins/leads that should be connected to ground. All of these should read dead short. Then, connect one probe to the Vcc (power/positive) input and use the other probe to check it correctly feeds the 5V regulator. Then repeat this process but use the 5V output of the regulator as the new reference and ensure correct connection for the applicable components to the supply rail. That's probably the simplest way to check rail and ground integrity. You can then test the individual signal/data connections.
    Last edited by darb1972; 11-01-2018 at 20:59. Reason: Brain Farts. Lots of them. Still yet to have coffee.
    Darb

  2. #22

    Default

    I haven't yet tried the 10k on the PICAXE side of the boards. If this was the case, would it be creating a voltage divider? If so I think that may be a cause of the problem as I have both resistors on either side the FRM010 chips input pin. If this doesn't work Ill use the multimeter and get some pictures.

    Thanks for the hep so far! I will try this out tomorrow and see if there is any progress
    Last edited by ojd233; 11-01-2018 at 22:12. Reason: Mistakes were made

  3. #23
    Technical Support
    Join Date
    Jan 1970
    Location
    UK
    Posts
    23,878

    Default

    Quote Originally Posted by ojd233 View Post
    I haven't yet tried the 10k on the PICAXE side of the boards. If this was the case, would it be creating a voltage divider?
    Yes it would.

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •