• AVR Freaks

Hot!How do I turn off power from PK3

Author
crosland
Super Member
  • Total Posts : 1586
  • Reward points : 0
  • Joined: 2005/05/10 10:55:05
  • Location: Bucks, UK
  • Status: offline
2019/01/19 08:56:49 (permalink)
0

How do I turn off power from PK3

Following on from my earlier issue https://www.microchip.com/forums/m1052285.aspx I struggled to get the PK3 to NOT power the device after deselecting the power in the tools options in MPLAB X
 
I now need to connect the board (a daughter board) to it's powered host and I DO NOT want the PK3 driving the power.
 
I have unplugged and plugged the USB cable but every time I connect the PK3 to the board the board LEDs light up showing that it is being powered. I can even program the device WITH NO POWER applied and the Power target circuit from PICkit 3 option UNTICKED.
 
It seems the only way to change the setting is to shutdown MPLAB X every time you change the programmer settings.
 
I have held off using MPLAB X and XC8 for many years now. Now what do I find? It's STILL a stinking pile of c**p!!!
 
MPLAB X 5.10 BTW
#1

4 Replies Related Threads

    du00000001
    Just Some Member
    • Total Posts : 2887
    • Reward points : 0
    • Joined: 2016/05/03 13:52:42
    • Location: Germany
    • Status: offline
    Re: How do I turn off power from PK3 2019/01/20 13:08:06 (permalink)
    0
    Could be you "shot" the switch controlling the target supply. (IIRC a MOSFET, easily damaged by ESD, usually ending up in the permanent-on state.)
    Setting the output voltage of the PK3 to a value somewhat lower than the target's own supply would make sure the PK3 doesn't really supply the target, but with a damaged control switch this might have limited impact.
    post edited by du00000001 - 2019/03/21 17:36:15

    PEBKAC / EBKAC / POBCAK / PICNIC (eventually see en.wikipedia.org)
    #2
    crosland
    Super Member
    • Total Posts : 1586
    • Reward points : 0
    • Joined: 2005/05/10 10:55:05
    • Location: Bucks, UK
    • Status: offline
    Re: How do I turn off power from PK3 2019/01/21 02:54:50 (permalink)
    0
    There's no damage.
     
    As I said, it works fine after closing and restarting MPLAB X. It's having to do this that is annoying.
     
    It also works fine with MPLAB 8.
    #3
    christinaz
    Starting Member
    • Total Posts : 32
    • Reward points : 0
    • Joined: 2018/05/17 09:58:42
    • Location: 0
    • Status: offline
    Re: How do I turn off power from PK3 2019/03/21 17:32:42 (permalink)
    0
    There is a note under Project properties> Conf>PICkit 3>Option Categories>Power:
    Selects the target Vdd voltage level that PICkit 3 will provide. This setting will NOT take affect immediately after being applied. Instead it will occur the next time MPLAB communications with the tool (e.g. by programming/reading/running etc.).
    As I understand, either you unplug then plug the PICkit programmer, or restart MPLABx to make your setting effective.
    #4
    Mysil
    Super Member
    • Total Posts : 3326
    • Reward points : 0
    • Joined: 2012/07/01 04:19:50
    • Location: Norway
    • Status: offline
    Re: How do I turn off power from PK3 2019/03/21 20:03:54 (permalink)
    0
    Hi,
    You might try to click the 'Hold in Reset' button in the row of Icons along the top of the MPLAB X window,
    after having changed settings in 'Project Properties'.
     
        Mysil
    #5
    Jump to:
    © 2019 APG vNext Commercial Version 4.5