ICD2 USB clone - how to get it to work with 3.3V PIC24s ???

[Gobol]

icd2 3.3v

Hi,
I've got simple question - how to programm 3.3V PIC24/dsPIC33F with "our" ICD2 USB clone ?
I'd add that when I downloaded PIC24 firmware into ICD2 it didn't pass the self test. I t seems that there is a possibility of getting it work with new chips.
Maybe simple header with some kind of voltage-level-changer would do the trick?

 

[Gobol]

icd2 usb clone

Anybody tried to do this ?

 

[potyo]

icd2 usb

When i select an 24F or 33F device, after downloading the new os passes the self test. But i don't have these devices, so i don't know that icd programs these devices or not.

 

[manu]

icd2 pic24

Simply switch the power supply, no ?!

 

[potyo]

usb icd2 clone

Simply switch the power supply, no ?!

what power supply? When you select an 3.3V device, powering the target device from icd2 is automatically disabled. If you have approx. 3.3V on the targets vdd pin, the self test must pass.

 

[Gobol]

icd2 clone 3.3v

Hmm... I've tried to do self test without target board connected to ICD.... Maybe here is the clue..
So, the edaboard's ICD2 clone should work with new 3.3V PICs...

 

[potyo]

icd2 clone usb

I haven't connected target to the icd, but through the protection diodes in the 74hc12x buffers when the pgd or pgc is high, there is approx 3.8V on the vdd pin. Look for my schematic at the

What is in the settings at the targets vpp, vdd, ...

 

[Gobol]

dspic33 icd2

I've created exactly the same project but on my own PCB. (btw: thanks for the sch).
Target Vdd - 0.00V
Target Vpp - 4.99V
MPLAB ICD2 Vpp - 12V

Self-test :
Target Vdd - Low
Module MCLR Vdd - Low

But I think it can be the problem because I have 74126 in HCT version... and I think I should replace it with HC (cmos level) one...

 

[be_jouster]

icd2 3,3v

Hi, all. I just get my Explorer 16 Board, the same problem still stuck in my mind. Is it OK to connect ICD2 Clone (Lothar version) that powered by +5V to the PIC24 & dsPIC33 that have lower operating voltage? If can, how to do it? Can I just separate both power supply (+5V for my ICD2 clone, +3.3V for my target device and of course with common ground)? Next thing, is it PGC & PGD on the target device (PIC24 & dsPIC33) can handle voltage signal more than +3.3V for example +4.7V with no harm to the target itself?

Best regards.

Added after 42 minutes:

I've tried download ICD2 24F-33F firmware OS to my ICD2 Clone and the result something like this:

Connecting to MPLAB ICD 2
...Connected
ICDWarn0030: MPLAB ICD2 is about to download a new operating system. If MPLAB IDE is just starting, it will appear to "hang" at the splash screen. Please be patient. MPLAB IDE will finish it's intialization after the OS is downloaded. (Note: You may wish to select to ignore this warning in the future.)
Downloading Operating System
Connecting to MPLAB ICD 2
...Connected
Setting Vdd source to target
ICDWarn0020: Invalid target device id (expected=0x40D, read=0x0)
...Reading ICD Product ID
Running ICD Self Test
...Passed
...Download Operating System Succeeded
Setting Vdd source to target
ICDWarn0020: Invalid target device id (expected=0x40D, read=0x0)
...Reading ICD Product ID
Running ICD Self Test
...Passed
MPLAB ICD 2 Ready

It has passed self test. But at Power tab it show:

Target Vdd = 5.00V
Target Vpp = 4.31V
MPLAB ICD2 Vpp = 12.62V

Is it okey?

Best regards.

 

[Gobol]

dspic33f icd2

Look at the programming specification datasheet.... New 24/33 PIC's no longer require 13V Vpp... they're programmed by pulling MCLR high (3.3V - as far as I concern) and transmitting specific patterns via PGD/PGC to enable programming mode.

I don't know is it safe to put 4.7V on the lines... I personally think it's not... but I'm exploring new possibility : to buffer lines with 74LVC244 or 245 dual-octal-transceiver.
LVC can be used to convert 5V levels to 3.3V, (but how to cope with data transmittion direction... )
maybe using simple 3.3V zeners and transistors would do the trick... ?

If anybody has some clues, please post them. It would be very helpful.
How it is done in original ICD2 ?

 

[potyo]

icd2 dspic33

For PGD and PGC lines you can use 74AHC126 buffers in icd-->target direction (HC126 is not suitable, because it has protection diodes between input pins and vdd), and HCT125 or AHCT125 buffers in the opposite direction. The HCT series has TTL compatible inputs, and they senses the >2V input signals as logical 1. You must supply the AHC chip from the targets vdd. My last schematic has these features, check it. However i don't know anything about the vpp.

 

[be_jouster]

icd2 pic24

I found this when I go thru the pic24 & dspic33 datasheet. All PGC & PGD are schmitt trigger input. Maybe we can think something here.....i hope..:|

 

[Gobol]

mplab ic2 device id 0x0

Ok, but what to do with MCLR ?
PIC24 need Vih level of MCLR to enter into programming mode. Refer to fig.3-3 of DS39768A-page 10.
h**p://ww1.microchip.com/downloads/en/DeviceDoc/39768a.pdf

Maybe new firmware wouldn't set MCLR to Vpp (13V) but only to Vdd (release from reset - mode) ?

In this case the new device should be programmed with 5V levels... I guess I would try...

 

[potyo]

pic24 icd2

If i select an 24F device, my icd2 sets the targets vpp voltage to 5V.

 

[Gobol]

icd2 3v3

have you checked this by multimeter or via programmer status window ?

 

[potyo]

usb 3,3v

Both

 

[polymath]

3.3v icd2

Check ICD Header ???.pdf DS51292L-page 5
https://ww1.microchip.com/downloads/en/DeviceDoc/ICD2_Header_51292L.pdf

It is clear that you cannot use ICD2 bufferless Clone directly on 3v3 devices.

Why not start thread to design a Header (RJ12/Header/RJ12) which directly connects to a standard 5v ICD2 with buffer/level converters on-board, which provides 3v3 supply and programming buffers?

Polymath

 

[be_jouster]

icd2 programming 3.3v

In the IC2 clone, between RC4 and RC5, whice is input and whice is output? Just to know.

Thanks..

 

[bendjy]

cloning usb id

Hi All

In my ICD2 clone with 18f4550 I use SN74lvc1t45 as in/out buffer. I don't have 3,3V PIC and I do not know this is solution for these PIC's. For 5V PIC work fine.

sorry for english

Regards
bendjy

 

[polymath]

ic2+4550+clone+firmware

Here is an interesting article to add confusion:

**broken link removed**

Are any level translators necessary on data and clock?

still seaching for an answer ........ Polymath