# Why erasing my PIC with PICKit2v2 doesn't work?

Below you can see the output of PICKit2V2 after clicking the Erase button:

As you can see above, all the memory addresses (I scrolled also) are equal to 3FFF.

Now when I click on the Read button, this is the output:

Scrolling:

As you can see above, the erasing didn't work fine. Does this mean my PIC is dead or something?

• Does Blank Check claim it's blank? – Majenko Jan 2 '15 at 15:36
• @Majenko Nope, It say that : Program Memory is not blank starting at address 0x000000 – Abraham Jan 2 '15 at 15:45
• What voltage are you powering the chip with? – Majenko Jan 2 '15 at 15:47
• @Majenko I don't powered the chip. My programmer use USB port as its power supply. So I can say 5v!? – Abraham Jan 2 '15 at 15:48
• Try running the program As Adminsitrator. If that does not work, it is either your PIC or Programmer faulty/dead... – Triak Jan 2 '15 at 15:56

A bulk erase is sensitive to the chip power supply voltage. According to the datasheet:

When using ICSP, the part must be supplied at 4.5V to 5.5V if a bulk erase will be executed.

It could be that your USB supply, once fed through the programmer, is dropping below 4.5V. While it's enough to program the chip, it's not enough to erase it.

You can try powering the chip separately from an external 5V power supply to see if that then allows you to erase the chip.

• using a 6 volt power supply can make any problem? I have a power supply that its output is 5.85 v. – Abraham Jan 2 '15 at 15:59
• 6V is good. According to the datasheet (you should read it some time), Vdd can be anywhere between -0.3 to +7.5V. +5.5V is the recommended maximum but it can cope with (at least for short periods) with up to 7.5V. – Majenko Jan 2 '15 at 16:02
• I know that this voltage is good for MCU. I was meant 6v couldn't make any problem with my USB port? Using another auxiliary power supply on MCU-pins is equal to Parallel 6v with USB port, is not it? – Abraham Jan 2 '15 at 16:07
• There will be a diode (or similar device) in the programmer's USB connection to stop back-powering. – Majenko Jan 2 '15 at 16:10
• There is a green LED on the programmer's board that when I connect the power supply to PIC pins, It turns off!Any comment? – Abraham Jan 2 '15 at 16:17