JTAG, short for Joint Test Action Group, is a method used for boundary scanning. Possibly applications are hardware testing/debugging and firmware flashing, including debricking of hardware which ended up in a defunct state.
Questions tagged [jtag]
42 questions
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2 answers
Flash Reading by JTAG
I'm trying to read the flash memory of a microcontroller MPC5606B from Motorola. I saw his pins and saw that it uses jtag to perform debug, so I'm trying to use it JTAG interface to read its flash content.
I read the MPC's flash content using a tool…
Daniel
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JTAG Version 2.0 or 2.1
I need to identify which device has JTAG Version 2.1 for TI TMS320DM8168CCYG4 (Digital Media Processor). What socket is recommended?
Charlie Polidoro
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Help required to figure out the JTAG or UART pins
I have an old CDMA dongle lying around, so I thought to try to reverse engineer them, but am unable to figure out the UART or JTAG pins, I have attached a photo of the probable pins, can anyone help on how to confirm.
This is the link to the FCC…
Raghav Varmani
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JTAG finding BS registers for IC's pins
On the internet, it always shows that each pin of the IC has its own Boundary Scan register (the yellow boxes)
But looking at BSDL files there are actually more BS registers than pins.
So for the questions:
Is it right to say that there are always…
menotyou
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OpenOCD, Buspirate JTAG reads fail after short time
I have a board that I'm reversing - and attempting to dump the image out of the NAND flash.
Board has a SAMSUNG s3c2440 SOC CPU, and there's a SAMSUNG k9f1g08u0d 128 MB NAND flash device.
I'm using a BusPirate through JTAG to connect. I am able to…
doe0731
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cheap BGA x-ray machine?
I want to look under a BGA chip and map JTAG pins to traces where I can attach a JTAGulator. Is there some version of a BGA x-ray that isn't thousands of $'s?
Here's a picture of the BGA's. Would it be easier to build a breakout connector to insert…
batflaps
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NAND flash programming over host MCU JTAG
We starting mass production of a custom device. It uses Chinese MCU LT1901. MCU core is arm926ej-s.
MCU boots from NAND flash. We are forced to program NAND flash before soldering on PCB.
I don't like it. I want to have a way to program NAND after…
uriy
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1 answer
Extracting Keyboard Firmware
I am trying to find out how to extract firmware from a Bluetooth keyboard, my understanding is that I would have to JTAG to retrieve the the firmware from the device is that correct? Also has anyone successfully done this in the past that might be…
Larry
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How can I differentiate the JTAG pins like TMS, TDI, TDO, & TCK using impedance
How can I differentiate between the JTAG pins like TMS, TDI, TDO, & TCK using impedance?
Because when we connect JTAG (RS422) with unnamed pin, we got a problem. So I am asking how to identify pins using impedance between pins and GND pin.
