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Hi,
target MAX10: 10M02SCU169
Quartus: 15.1
I was trying to use JTAG sharing on MAX10 so I checked "enable JTAG sharing" and unchecked "enable nCONFIG, nSTATUS, CONF_DONE" and generated JTAG-sharing-fw1 putting JTAG pins to hi-z in user mode.
The JTAGEN is pulled-up always (so JTAG-port should always be active)
I succeed to upload JTAG-sharing-fw1 to MAX10 but immediately after I don't get access to JTAG-port anymore: JTAG-Autodetect command from Programmer-windows is not working anymore and MAX10 device is not recognized "unknown device".
I repeated this test with 3 more boards, all fails the same: they work correctly with any firmware where JTAG sharing is disabled.
I suspect that JTAG-sharing-fw1 is preventing the JTAG-port to work correctly and that for some reasons, JTAGEN is perhaps not correctly sampled (I didnt try to toggle the JTAGEN to see if anything happens)
My questions:
1st q: i want to erase the jtag-sharing-fw1 image from max10 and get back an "empty" MAX10
Could you please tell me which is the procedure?
As far as I could understand, after poweron, I have to set nCONFIG to low and hold it. This will set MAX10 in reset mode so preventing JTAG-sharing-fw1 to be loaded.
While nCONFIG is hold low (FPGA in RESET state) will JTAG-Autodetect command work?
Should I drive nSTATUS and CONF-DONE as well? how?
L
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Hi, got some info reporting this bug on Quartus from here: " Why can’t I access the MAX 10 device via JTAG even though JTAGEN is pulled high in user mode?"
https://www.altera.com/support/support-resources/knowledge-base/solutions/rd03222016_95.html and here: "How do I gain access to the JTAG pins of my MAX 10 device if I have enabled the JTAG pin sharing option, and the Quartus Prime Programmer is unable to auto detect the device?"
https://www.altera.com/support/support-resources/knowledge-base/solutions/rd05192016_963.html In my design, nCONFIG-nSTATUS-CONF_DONE are connected to CPU-GPIOS; so
after poweron, I tried to assert-low nCONFIG and hold it low and tried to access JTAG-port with Quartus programmer Autodetect; it doesnt work. Same if I assert-low all signals nCONFIG-nSTATUS-CONF_DONE
My question is:
To erase fw we must force a fw-reload which is triggered by following events (ref to m10_handbook.pdf at page 477)
"........ Reconfiguration is triggered by the following actions:
• Driving the nSTATUS low externally.
• Driving the nCONFIG low externally.
• Driving RU_nCONFIG low."
since in the JTAG-sharing-fw1 generation I have enabled JTAG-sharing and DISABLED nCONFIG-nSTATUS-CONF_DONE, such pins wont work anymore so it is normal that this procedure must fail.
Since nCONFIG is disabled, how to get control back on the JTAG-port?
BR,
L
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