Nonce - Fixed

A fixed nonce is passed to the device and stored in one of the internal buffers. The size of the nonce may be either 32 or 64 bytes. The TempKey.SourceFlag is always set to input after this command is run. This mode of the Nonce command does not run a SHA256 calculation or generate a random number.

Table 1. Fixed Nonce Input Parameters
Opcode Mode Param2 Data Description
0x16

0x03
0x43
0x83

0x00 32 bytes
  • 32 bytes written to TempKey
  • 32 bytes written to Message Digest Buffer
  • 32 bytes written to Alternate Key Buffer

0x23
0x63

0x00 64 bytes
  • 64 bytes written to TempKey
  • 64 bytes written to Message Digest Buffer
Table 2. Fixed Nonce Output Response
Name Size Description
Response 1 byte 0x00 if the command is completed successfully. Otherwise an error code is received.
Notes:
  1. 1.TempKey.SourceFlag is set to ‘1’ upon successful command completion, indicating nonce value was fixed input value.
  2. 2.TempKey.Valid is set to ‘1’, indicating the value is valid for other use.