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AR# 56272

Zynq-7000 SoC - PROG_B must be pullup during BootROM execution in production silicon


If during boot the PROG_B signal is held LOW, the BootROM  waits while trying to clear the PL.

Only after a timeout (few minutes long) the BootROM goes in Secure Lock Down.

The user will not be able to see the DAP in the JTAG chain.

This behavior is different from GES where the DAP is available even if booting with PROG_B LOW.

Visit Zynq-7000 SoC Solution Center (Xilinx Answer 52512) to address all questions related to the Zynq-7000 SoC.


Be sure that PROG_B is pulled up (HIGH) during boot.

Linked Answer Records

Associated Answer Records

AR# 56272
Date 05/28/2018
Status Active
Type Known Issues
  • Zynq-7000
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