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22 lines
707 B
Plaintext
22 lines
707 B
Plaintext
# uds
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Unique Device Secret core
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## Introduction
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This core store and protect the Unique Device Secret (UDS) asset. The
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UDS can be accessed as eight separate 32-bit words. The words can be
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accessed in any order, but a given word can only be accessed once
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between reset cycles. The words can only be accessed as long as the
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fw_app_mode input is low, implying that the CPU is executing the FW.
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Each UDS words has a companion read bit that is set when the word is
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accessed. This means that the even if the chip select (cs) control
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input is forced high, the content will become all zero when the read
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bit has been set after one cycle.
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## Implementation
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The UDS words are implemented in discrete registers.
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