ATF280F_14 datasheet(54/107 Pages) ATMEL

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ATF280F [DATASHEET]

7750E

−AERO−05/12

Figure 5-22. Management of configuration download link protection

5.4.3.1 Low level Errors management

These errors have the highest priority and terminate by a configuration download abort. They are managed in the same

way whatever is the used parallalel mode (Mode 2 or 6).

The low level errors are detected in case of bad values regarding the following elements:

• “Preamble” mismatch

different from “10110111”

• “Start Address” mismatch

if the start address of a window is corrupted,

• “Stop Address” mismatch

if the stop address of a window is corrupted,

• “Postamble” mismatch different from “11100111”.

In case of low level error, INIT is driven low during one CCLK clock period few clock cycles after the byte in default.

Then, INIT is released and CON is released. The configuration download is so finished.

5.4.3.2 Checksum Errors management

During the generation of an application bitstream, a checksum is computed with a specific algorithm by IDS tool and

stored in the bitstream checksum zone. This checksum is the reference for checksum error management.

All along the configuration download, the “configuration load checker” calculates on-the-fly a checksum byte by

accumulating all effective data of the downloaded bitstream with a hardcoded algorithm.

ATF280F bảng dữ liệu(PDF) 54 Page - ATMEL Corporation