Forum Discussion

liron87's avatar
liron87
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5 years ago

JTAG pin sharing in MAX10

I would like to know if I can use the option of JTAG pin sharing "on the fly" by toggle JTAG_EN pin (switch back and forth between user I/O pins and dedicated JTAG pin)?
NurAiman_M_Intel's avatar
NurAiman_M_Intel
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5 years ago

Hi,


JTAGEN is a dual-purpose pin. This pin functions according to the setting of the JTAG pin sharing option bit. If the JTAG pin sharing is not enabled, the JTAGEN pin is a regular I/O pin and JTAG pins function as JTAG dedicated pins.


If the JTAG pin sharing is enabled and the JTAGEN pin is pulled low, JTAG pins function as dual-purpose pins. If the JTAG pin sharing is enabled and the JTAGEN pin is pulled high, JTAG pins function as JTAG dedicated pins


Hence, if the pin is dedicated pin, it can't be used using user I/O mode.


Regards,

Aiman


liron87's avatar
liron87
Icon for New Contributor rankNew Contributor
5 years ago

Hi,

I'm using 10M08 Evaluation Kit with the following configurations:

- JTAG pin sharing is enabled

- JTAGEN pin is pulled high

- FPGA sample JTAG pins as inputs regardless to JTAGEN state and I can't access JTAG (can't access the device) .

It doesn't fit with the configuration user guide

The only solution for access the device is to erase CFM while nconfig low

Please advise

Thanks,

Liron