0 1 2 Secure Write Sequential Request Include a digital signature along with the control data Algorithm Algorithm used to compute the digital signature For future proof NONE No digital signature For test purposes only AES-GMAC-64 64 bit AES signature algorithm is used ECC-256 256 bit ECC signature algorithm is used Timestamp Timestamp value is the number of seconds since January 1, 2000 Milliseconds Millisecond counter 0-999 Sequence Sequence number of request Shall be advanced for each request Offset Starting offset for write operation X values to follow Role Signing key used 0-5 Each controller is assigned a key index that maps to their access control role N Number of registers comprising the digital signature. The value of N must be at least 4 (64 bits) X Number of (offset, value) pairs being written A max of 50 (offset, value) pairs are allocated Value1 Value to write to control register at offset DS Digital Signature The DS covers all registers from X to N and is N registers in length