Recent content by JamesUWF

  1. J

    microprocessors

    I learned everything I know about the 8085A from these two books: Intel 8085A User's Manual  (Intel Corporation 1985) http://www.bugbookcomputermuseum.com/8085A-Cookbook.html James
  2. J

    Rechargeable Fan - Paintball Mask

    Pet Monster, Have you taken a look inside your computer to see if there are any devices that regulate current to USB ports?  Maybe something like a TPS2032D, or similar?  If so, there is a chance it will have an OC output that is asserted when an overcurrent or thermal shut down occurs.  You...
  3. J

    Rechargeable Fan - Paintball Mask

    Might be easier just to use a thermal lens with your mask, if you haven't already. James
  4. J

    QVGA LCD + touchscreen implementation

    You don't necessarily need a LCD controller.  If you want to display video or  VGA input, a COTS controller board would be an easy way to go.  If you are just going using it as a GUI, then you can probably drive it with TTL signal levels.  Does your controller board have any type of VGA or NTSC...
  5. J

    How can i use a common cathode 7segment as a common anode 7segment display

    I suppose you could, if you ran each of the 7447 outputs (a-g) through inverters, if you have some 7404's handy, before the resistors and LEDs. 
  6. J

    Current Regulator Circuit

    If push comes to shove, that's what I'll do, but I was hoping to make it pull the same current regardless of any voltage change on the supply under test,  using the feedback loop.
  7. J

    Current Regulator Circuit

    I did consider doing that with an inverting op-amp, but the control voltage I'm generating for the negative current regulator circuit is already taken from a -12V supply, thus already negative.  Wouldn't this be the same as inverting a positive control voltage?
  8. J

    Current Regulator Circuit

    Sorry guys, those came out blurry.  Here are the JPGs.
  9. J

    Current Regulator Circuit

    Hey guys, I'm working on a circuit that is an adaptation of something I found online awhile back.  The first adaptation of the original circuit I made (shown below) draws a fixed amount of current from a positive voltage external supply.  The idea is that the amount of current flowing through...
  10. J

    Re: 8085 weird problem

    Correction.  I meant to say "...the "DCX rp" instruction does not affect any condition flags..."
  11. J

    Re: 8085 weird problem

    I'm not sure what kind of 8085A emulator you are using, but a real life 8085A will fetch and execute whatever instruction the Program Counter points to, be it "DCR M" or "DCX rp."  Either of these instructions can be used to decrement a 16-bit number, but if you examine the instruction set...
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