can i use any JTAG device with these micros? for example Silicon Labs JTAG
OutThere
Last Edited: Fri. Feb 25, 2022 - 02:18 PM
JTAG question
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grohote
OutThere wrote:
can i use any JTAG device with these micros
If this means: Is it possible to JTAG debug an AVR and other device in a chain-
the answer is: yes (but, I did not try).
awneil 
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OutThere wrote:
can i use any JTAG device with these micros?
Which micros, exactly? Note that not all AVRs have JTAG:
(so it might be more accurate to say that most AVRs don't have JTAG?)
OutThere wrote:
for example Silicon Labs JTAG
JTAG is just a low-level specification - above that there are device-specific issues.
Also, the interface between the JTAG probe and the host system is not (necessarily) standard.
eg, Microchip Studio isn't going to recognise an SiLabs JTAG probe.
ki0bk
OutThere wrote:
can i use any JTAG device with these micros?
That would depend on what "these micros? means, not all AVR's have a JTAG interface, in fact, most do not.....
clawson 
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Bottom line is NO you cannot use a different manufacturers JTAG even on AVRs that say they have "JTAG". You have to get the Atmel device. That is because, although JTAG is an "open standard" the "data protocol" for debugging that passes over the wires is a proprietary protocol known only to Atmel and implemented by the firmware in their own JTAg interfaces.
These days most would start with Atmel-ICE or (because Microchip have "assimilated" Atmel) the Microchip PickKit 4. If you plan to work in Windows and use Studio 7 then Atmel-ICE is probably the "better" choice. If you plan to work in MPLABX (probably because you use Linux or MacOS) then the PickKit may be the better alternative (though it's true that each device is supposed to work with the "other" IDE as well).
awneil
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Apart from Atmel-ICE, there's also the EDBG on Xplained & Curiosity boards; eg, https://www.avrfreaks.net/commen...
Out of interest, are there any 3rd-party "generalist" JTAG probe manufacturers that support AVR?
can't say I recall ever hearing of any
Segger are probably the best-known 3rd-party - and they do not list AVR:
Although there is:
gchapman 
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clawson wrote:
There are third party efforts on decoding AVR JTAG debug instructions.
That is because, although JTAG is an "open standard" the "data protocol" for debugging that passes over the wires is a proprietary protocol known only to Atmel and implemented by the firmware in their own JTAg interfaces.
clawson wrote:
Device packs' top level will have a list of tools for each device.
(though it's true that each device is supposed to work with the "other" IDE as well).
JTAG Debugger (ECE 4760) (Cornell University)
Atmel Packs (Microchip Studio)
Microchip Packs Repository (MPLAB X)
awneil
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gchapman wrote:
Device packs' top level will have a list of tools for each device.
Also the Product Page (although seems only Microchip's own products are listed); eg,
https://www.microchip.com/en-us/product/ATmega128#document-table
Of those, the SNAP would be the cheapest:
js 
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The avatr is interesting, it looks like a National semiconductor debugger with 2 x 8" floppies from about 40 years ago.
grohote
js wrote:
The avatr is interesting, it looks like a National semiconductor debugger with 2 x 8" floppies from about 40 years ago.
Close enough /by the age/, it is Digital PDP-8/e
ki0bk
Last Edited: Fri. Feb 25, 2022 - 09:59 PM
grohote
I should recall my PDP, can it be Terminal DEC-VT52 instead?
TRS-80, it is.
Advertised that 'can do anything', yet failed on a simple sorting of the edited text.
Last Edited: Fri. Feb 25, 2022 - 10:14 PM
Jeckson
gchapman wrote:
JTAG Debugger (ECE 4760) (Cornell University)
WayneZA 
js wrote:
National semiconductor debugger with 2 x 8" floppies from about 40 years ago.
Ahh, them thar' new-fangled magnetic doodads? They'll never catch on ...