Segger Flasher ATE, Руководство пользователя

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90 CHAPTER 9 Target board design
9.2 Target board design
We strongly advise following the recommendations given by the chip manufacturer. These
recommendations are normally in line with the recommendations. Please refer to the the
appropriate tables depending on the core:
•
Pinout JTAG on page 87
• Pinout SWD on page 88
In case of doubt you should follow the recommendations given by the semiconductor man-
ufacturer.
9.2.1 Pull-up/pull-down resistors
Unless otherwise specified by developer’s manual, pull-ups/pull-downs are recommended
to be between 2.2 kOhms and 47 kOhms.
9.2.2 RESET, nTRST
The debug logic is reset independently from the CPU core with nTRST. For the core to
operate correctly it is essential that both signals are asserted after power-up.
The advantage of having separate connection to the two reset signals is that it allows the
developer performing software debug to setup breakpoints, which are retained by the debug
logic even when the core is reset. (For example, at the reset vector address, to allow the
code to be single-stepped as soon as it comes out of reset). This can be particularly useful
when first trying to bring up a board with a new ASIC.
Flasher ATE User Guide (UM08035) © 2017-2018 SEGGER Microcontroller GmbH