7.2.3.3 Example for the calculation of SPDU_ID_1, SPDU_ID_2 and SPDU_ID_3 (informative)

Figure 22 shows a concrete example of the calculation of SPDU_ID_1, SPDU_ID_2 and SPDU_ID_3. The following input values were chosen for the calculation: SafetyBaseID is the GUID “72962B91-FA75-4AE6-8D28-B404DC7DAF63”, SafetyProviderID has the value 0xE0EA6B40, SafetyStructureSignature has the value 0xDE7329FD and the SafetyProviderLevel_ID is chosen as 0xDEAA9DEE (representing SIL 3).

See OPC 10000-6, 5.2.2.6 for details on the encoding of Guids. The octets from the resulting octet stream are used according to Figure 21, i.e. in “reverse order”.

The resulting SPDU_IDs are as follows: SPDU_ID_1 has the value of 0xAC3CB67F, SPDU_ID_2 has the value of 0x9495D388 and SPDU_ID_3 has the value of 0x87F13E11.

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Figure 22 (informative) – Example for the calculation of SPDU_ID_1, SPDU_ID_2 and SPDU_ID_3