If you look at the datasheet you will see that the PGEC2 and PGED2 are 5 volt tolerant pins. And hence can be connected to the junebug device that is a 5 volt device. The "dspic33f family reference manual" state thatI have a homemade clone of pickit2 with schematic
View attachment 52065
Can this clone program 3V3 pics (eg. dspic33fj64gp804)?
Any of the following three pairs of programming clock/data pins can be used:
• PGEC1/PGED1
• PGEC2/PGED2
• PGEC3/PGED3
During programming, each pin pair is recognized as a valid programming connection. Therefore,no special selection is to be performed by the user to specify which pin pair will be used forprogramming.
The debugging functionality is controlled through the PGECx (emulation/debug clock) and PGEDx (emulation/debug data) pin functions. Any of the following three pairs of debugging clock/data pins can be used:
• PGEC1/PGED1
• PGEC2/PGED2
• PGEC3/PGED3
The debugging clock and data pins must be selected by programming the ICD Communication Channel Select Enable bits (ICS<1:0>) in the In-Circuit Debugger Configuration register (FICD<1:0>). To use the in-circuit debugger function of the device, the design must implement ICSP connections to MCLR, VDD, VSS, and the PGECx/PGEDx pin pair. In addition, when the feature is enabled, some of the resources are not available for general use. These resources include the first 80 bytes of data RAM and two I/O pins
I have done this andI have following error:Maybe just give it a try with no PIC attached with settings for the 33F PIC and measure VDD and VPP.
It might detect there is no PIC connected too quickly to get a measurement, but worth a try.
Yes that is correct. In your schematic the power to the ICSP port. Comes dirrectly from the USB 5 volt power rail. And hence it can not power any 3.3 volr device without inserting a LDO. But doing so. You should be able to power at least your dspic33fj64gp804 as it has some 5 volt tolerant pinsI have done this andI have following error:
Initializing PICkit 2 version 0.0.3.63
Found PICkit 2 - Operating System Version 2.32.0
Target power not detected - Powering from PICkit 2 ( 3.25V)
PK2Error0024: PICkit 2 was unable to establish a valid Vdd on the target (Attempted 3.25V - Read 4.99V)
PICkit 2 Ready
The question still remains my clone has a problem or the schematic is not made to power 3V3 pics.
Did you mean VPP and not VDDCould be a solution not to connect VDD at all and use only development board power supply the dspic, I will try.
One more question, is it possible by mounting one of transistors BS250 /2n7000 wrong can have this behavior: 0/5V on VDD output?
Thank you.After another look the junebug is actually missing some of the parts for controlling the voltage of VDD, so you get only 5V on the ICSP connector and about 4.8V on the ICD connector which can be switched on or off using Q2 and Q5.
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