ProDevelopBoard

Comments

• Jon Williams Posts: 6,491

  2006-05-09 00:51 edited 2006-05-09 00:51

  1. No, each LED already has a 470.
  2. All LEDs on the board are common cathode. For the 7-segment LEDs, you must make the selected digit cathode line (X18) low (Vss).
  3. Yes.
  
  If you're connecting RB to X17 you'll want to connect one of the X18 lines (digit select) to Vss; after that you can display digits/characters on the 7-segment LED -- a "1" lights the LED.
  
  ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
  Jon Williams
  Applications Engineer, Parallax
• John.Gray Posts: 22

  2006-05-09 01:24 edited 2006-05-09 01:24

  Thanks Mr. Williams
• Jon Williams Posts: 6,491

  2006-05-09 02:08 edited 2006-05-09 02:08

  No problem -- any you can call me "Jon."
  
  ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
  Jon Williams
  Applications Engineer, Parallax
• Chris Savage Parallax Engineering Posts: 14,406

  2006-05-09 03:27 edited 2006-05-09 03:27

  John.Gray said...(trimmed)
  3.· I noticed that each sub section of the PDB has a double row for the header, I assume that these are connected.

  John,
  
  ·· One exception to the double row sockets being connected is the LCD connector.· Each row on 4 of the pins connects to different address lines on the LCD Display.· May not be a big deal but just in case.
  
  ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
  Chris Savage
  Parallax Tech Support
  csavage@parallax.com
• Jon Williams Posts: 6,491

  2006-05-09 04:03 edited 2006-05-09 04:03

  Thanks for the catch, Chris -- you're right, and the LCD data buss connections need to be wired very carefully.
  
  ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
  Jon Williams
  Applications Engineer, Parallax
• Chris Savage Parallax Engineering Posts: 14,406

  2006-05-09 05:23 edited 2006-05-09 05:23

  Easy to miss...It just happens I have recently used all 8 data lines and it was foremost in my mind.
  
  ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
  Chris Savage
  Parallax Tech Support
  csavage@parallax.com
• John.Gray Posts: 22

  2006-05-09 15:44 edited 2006-05-09 15:44

  I have noticed on the push button switches on the PDB there is slots for Vdd and Vss, like the LED question above, do I need to connect the switches to Vss or Vdd, the instructions say it's wired in an active low config, just wondering why the Vss and Vdd are right next to the push buttons. It's almost tempting me to plug a wire in there. I am starting to really like the PDB my only comment is about the information put out on the info sheet. As someone is is self learning I enjoy all the info Parallax puts out for the BS2, it just seems with the SX/B and the PDB not as much attention has been given to these products.
• ellizard Posts: 106

  2006-05-09 17:14 edited 2006-05-09 17:14

  Hi John
  
  I recently got a PDB and I found very useful before starting to use it to have a very deep look at the PDB schematics.
  
  You can find it here: http://www.parallax.com/dl/docs/prod/boards/PDBSchem.pdf
  
  It is well divided into the various sectors of the Board.
  From that schematics it will be obvious to you what's the meaning of active-low logic.
  the blocks marked with VIN, VDD and VSS around the protoboard, are other supply blocks to provide local·powering.
  
  
  Hope this is of help
  
  Post Edited (ellizard) : 5/9/2006 5:35:31 PM GMT
• Jon Williams Posts: 6,491

  2006-05-09 17:25 edited 2006-05-09 17:25

  The push-buttons and dip switches on the PDB are wired active-low (that is, they are pulled up to Vdd through 10k). The Vdd and Vss connections are for convenience for components on that side of the breadboard.
  
  ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
  Jon Williams
  Applications Engineer, Parallax
• John.Gray Posts: 22

  2006-05-09 18:20 edited 2006-05-09 18:20

  I was unable to open the file yesterday before posting the questions. It really would have come in handy. How about you print it out and attach it to the documentation that is sent with the PDB? I am really liking the PDB, once you get over the sticker shock, someone really earned their paycheck at Parallax with this one. I don't like the Push button switches, other than using them as a quick down and dirty keypad, I wish there was a few slide switches (maybe 3?)as well, the DIP switches just aren't quit the same as the good ole slide switch. The other thing I would do is throw a few T-blocks for input of sensors like a PIR or something like that. I also think the LED's 0-15 should be a different color than the power and pulse generator.
• John.Gray Posts: 22

  2006-05-09 18:33 edited 2006-05-09 18:33

  I tried again and was unable to open the schematic file for the PDB.
• Jon Williams Posts: 6,491

  2006-05-09 19:35 edited 2006-05-09 19:35

  You may need to update your Acrobat reader.
  
  ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
  Jon Williams
  Applications Engineer, Parallax