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palcal

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Joined: 12/10/2011
Location: Australia
Posts: 1873

Posted: 06:11am 17 Oct 2023

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Just got a new SNAP programmer from Microchip. My Pickit 3 clone stopped working.
The new tool is recognised by MPLAB but when I try to connect I get this error.

Quote You have entered an invalid value (null) for the Voltage Level on the Snap Power property page

I can't find where to change the Voltage Level. I've searched Microchip for the answer but can't find anything.
HELP!!!

"It is better to be ignorant and ask a stupid question than to be plain Stupid and not ask at all"

bigmik

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Joined: 20/06/2011
Location: Australia
Posts: 2914

Posted: 08:39am 17 Oct 2023

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Hi PalCal,

Based on my using of the pickit3 there is a section in the menu for Advanced options that prompts for a password that brings up a menu

The password is

microchip

Maybe the setting is in there.

Regards,

mick

Mick's uMite Stuff can be found >>> HERE (Kindly hosted by Dontronics) <<<

barewires
Newbie

Joined: 13/04/2015
Location: United Kingdom
Posts: 30

Posted: 09:33am 17 Oct 2023

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According to the Microchip Forum:

https://forum.microchip.com/s/topic/a5C3l000000MebqEAC/t386157
Snap doesnt have any power output.

It relies on DUT having its own power supply.

palcal

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Joined: 12/10/2011
Location: Australia
Posts: 1873

Posted: 07:47pm 17 Oct 2023

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Yes I've read that and gone into advanced settings. In advanced settings you can only select high or low power programming. There is no provision anywhere to set a voltage value.

"It is better to be ignorant and ask a stupid question than to be plain Stupid and not ask at all"

palcal

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Joined: 12/10/2011
Location: Australia
Posts: 1873

Posted: 09:20pm 17 Oct 2023

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I changed chips and successfully programmed a PICMX170, I am trying to program a PIC16F1455 in a ZIF socket, so maybe not good contact, will look into it. I suspect the error about voltage is some sort of error in itself.

"It is better to be ignorant and ask a stupid question than to be plain Stupid and not ask at all"

zeitfest
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Joined: 31/07/2019
Location: Australia
Posts: 482

Posted: 11:54pm 18 Oct 2023

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IIRC the 16F1455 as supplied has a configuration bit set that prevents LVP by default, so initially HVP is needed, I think the SNAP is LVP only ?? (unless another voltage source is present ??)
Also 16f1455 uses different pins for LVP cf. HVP, maybe check the pins used for programming.

palcal

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Joined: 12/10/2011
Location: Australia
Posts: 1873

Posted: 03:35am 19 Oct 2023

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I now have a feeling the chip was already programmed, I have had the chips for years and maybe programmed them all when I received them. They are SOIC so I will have to solder one in and test it when the boards arrive.

"It is better to be ignorant and ask a stupid question than to be plain Stupid and not ask at all"

phil99

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Joined: 11/02/2018
Location: Australia
Posts: 2135

Posted: 07:24am 29 Oct 2023

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Modifying the Snap programmer to provide power.

Silicon Chip June 2021 page 69.

There are 5V and 3.3V pads near the voltage regulator, about 6mm apart.
Snip the middle pin off a 3 pin header socket, spread the pins a little to match those pads and solder to the pads.
Snip one end off a Dupont wire and solder it to pin 2 of the programming header socket.
Plug the other end into the required voltage.

amigawizard

Regular Member

Joined: 15/08/2023
Location: Australia
Posts: 43

Posted: 10:38am 29 Oct 2023

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27.2 Low-Voltage Programming Entry
Mode
The Low-Voltage Programming Entry mode allows the
PIC® Flash MCUs to be programmed using VDD only,
without high voltage. When the LVP bit of Configuration
Words is set to ‘1’, the low-voltage ICSP programming
entry is enabled. To disable the Low-Voltage ICSP
mode, the LVP bit must be programmed to ‘0’.
Entry into the Low-Voltage Programming Entry mode
requires the following steps:
1. MCLR is brought to VIL.
2. A 32-bit key sequence is presented on
ICSPDAT, while clocking ICSPCLK.
Once the key sequence is complete, MCLR must be
held at VIL for as long as Program/Verify mode is to be
maintained.
If low-voltage programming is enabled (LVP = 1), the
MCLR Reset function is automatically enabled and
cannot be disabled. See Section 6.5 “MCLR” for more
information.
The LVP bit can only be reprogrammed to ‘0’ by using
the High-Voltage Programming mode.

Wayne !

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