What is the difference between nSRST and nTRST / STK500 EXPAND0 wiring

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Hello!

 

I'm trying to connect an JTAG ICE mk II to an STK500 with an ATmega16  and, after looking at various schematics and verifying the connections with a multimeter, I came up with the following wiring:

 

 

JTAG Pin # JTAG Signal Name Atmega16 Port # Atmega16 Pin # Expand0 Pin #
1 TCK PC2 24 28
2 GND GND 11/31 1/2/19/20/39/40
3 TDO PC4 26 26
4 Vref AREF 32 14
5 TMS PC3 25 27
6 nSRST RESETn 9 15
7 Vsup VCC 10/30 21/22
8 nTRST RESETn 9 15
9 TDI PC5 27 25
10 GND GND 11/31 1/2/19/20/39/40

 

The issue I ran into is shown above.  I'm not entirely sure what nSRST and nTRST do or how to connect them to the STK500 (not sure if I wire them both up to nRESET, only use one of them and leave the other floating, or if I should connect it another way).  Can someone else help me fill in this knowledge gap so I can get debugging up and working on my board? 

 

Any help would be appreciated.  Thanks!

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nTRST is a JTAG machine reset ATmega16 has no JTAG reset pin so nTRST must be left unconnected.

 

Vref is not "ADC reference" but it is JTAG ICE mk II I/O buffers supply and must be connected to target (ATmega16) VCC line.

See User guide, page 27

wbr, ReAl

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The link for the jtagice is good, but is there a link to get all the help?  In the good old days, all I had to do is fire up Studio and click Help.  I could get help for the jtagice and for the Atmel ICE and for a hundred other things.   Is that still available?

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All the Atmel manuals are online and have succeed in the move to microchip.com. 

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How about a link.  If I see this again I will get my assault gun and blast a hole in my monitor.  angry

 

 

Last Edited: Sun. Apr 1, 2018 - 12:28 PM