Electrical Engineering Stack Exchange
Electrical Engineering Stack Exchange

Questions tagged [jtag]

JTAG is an interface that allows 1) testing of inter-chip connections 2) programming of Flash, microcontroller and FPGA devices.

Further reading:

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JTAG vs SWD debugging

After skimming through this article, I am wondering what are the benefits of SWD debugging over JTAG debugging? I understand SWD uses less wires/pins, takes up less space etc. But how does it play out in terms of performance, features and cost of…
josef.van.niekerk
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Programming microcontrollers: JTAG, SPI, USB oh my!?

I've noticed, with regards to microcontrollers, there are several way to program them. I am sorta familiar with USB as my Arduino's can be programmed via USB. What is a JTAG or SPI interface? Ultimately I know that these interfaces provide a means…
jdiaz
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What is a JTAG?

I'm pretty new to embedded systems, and I keep seeing this term used all the time, but I can't quite understand what is it. A quick search online yields this Wikipedia page: https://en.wikipedia.org/wiki/Joint_Test_Action_Group which describe it as…
UnTraDe
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Switch from JTAG to SWD with bitbang sequence on STM32F103VB

I am trying to switch from JTAG to SWD without any external devices. Why? Because I would like to use the SWO pin to send a stream of logging information to another device. To accomplish this without using an external debugger, I have connected the…
Heneer
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JTAG debugging AVR

Can anyone advise what hardware and software is required for debugging AVR in circuits?
JohnC
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Is it possible to make a JTAG interface with an arduino?

If so, could one direct me to a site that tells how to do this? I believe I may have found a way, but I am unsure as to whether or not it would work yet (need to find something to test it on). This question is related to a previous question of mine…
zec
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Cheap FPGA dev board

I want to begin with FPGA, but I've never worked with once before. I want a cheap kit, but I don't know where to start. I can find cheap boards, but then I can't get no information about the programmer or compiler, so I hope that you can help. I…
rnunes
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Why JTAG connectors are available in 10pins/14pins/20pins when JTAG is of 5pins

AFAIK, JTAG is requires 5 pins (Wikipedia article): TDI (Test Data In) TDO (Test Data Out) TCK (Test Clock) TMS (Test Mode Select) TRST (Test Reset) optional. Let's add two more Power supply Pins (Vcc and GND). If it is of 7 pins then why most…
Swanand
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Is there an open source USB to JTAG circuit I can include in my PCB design?

Im trying to find out if it would be possible to build/include a USB to JTAG circuit on my experiment circuit board I'm designing. My aim is not to reinvent the wheel, but use something that is already out there, and simple/small enough to add to my…
josef.van.niekerk
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Spy-Bi-Wire vs JTAG

I'm working on an MSP430 design and I'm very intrigued by the Spy-Bi-Wire two-wire programming interface. From what I read it is very similar in terms of functionality to JTAG and even looks better in some cases (less wires of course, but also…
Joel B
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What's the difference between a commercial JTAG debugger and an open source FT2232H OpenOCD debugger?

I have seen a few commercial JTAG debuggers such as: iC6000 On-chip Analyzer (with Aurora protocol support) Lauterbach – Microprocessor Development Tools And OpenOCD FT2232H-based JTAG debuggers: Flyswatter NGX ARM USB JTAG Why are these…
robomon
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SWDAP vs CMSIS-DAP vs DAPLink

EDIT : I got the basic questions (for example, what is CMSIS-DAP?) answered by user @Nipo. Based on that, I restructured my post in a more logical way. Hopefully the remaining questions will be answered as well :-)   1. Programming a…
K.Mulier
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Programming multiple FPGAs using JTAG

I have a JTAG chain connecting 4 Spartan 6 FPGAs that I program using ISE iMPACT. The software can program any strict subset of the 4 FPGAs in a row successfully, and in any order. However, when I attempt to program all four FPGAs, the DONE pin of…
Randomblue
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Boundary scan developer and testing tools

I have to choose a tool for production testing of fairly dense PCB's with 4+ FPGAs 10+ DSPs, ethernet controllers and PCI controllers.. Does anyone have any experience with any of the tools available from GOEPEL, XJTAG, Jtag-technologies or if…
Keh0082
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NRF52 Debug Connection - GndDetect and VTRef

I'm currently in the process of laying out a debug connector for an nRF52 chip. I'm planning on using the IDAP-Link. Most of the pins are pretty straight forward to connect (ie: for SWDIO I simply route that pin on the nRF52 uC to pin 2 on the debug…
Fuzzy_Bunnys
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