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• Assembling/Splitting FBs for (SAFE)BOOL/BYTE/WORD/DWORD

Assembling/Splitting FBs for (SAFE)BOOL/BYTE/WORD/DWORD

Type	Function blocks Available as standard (non-safety-related) and safety-related type (*_S). For the safety-related type, the safety-related data types (SAFE*) are expected at the formal parameters.
Description	The assembling function blocks are used to summarize binary signals to bit groups consisting of 8, 16, or 32 bits. To access the individual bits (BOOL) in a bit group, the group (BYTE, WORD, or DWORD) has to be split first using the splitting function blocks. Background: To improve the clarity of the safety logic and to process signals as a bundle, the individual binary signals (BOOLean variables) can be combined (summarized) to groups. These bit groups can then be handled as BYTE, WORD, or DWORD data type respectively.
Available function blocks	Assembly function blocks: SAFEBITS_TO_SAFEBYTE / BITS_TO_BYTE Description: Summarizes eight (SAFE)BOOL input variables to one (SAFE)BYTE output variable. Bit valence: In the output BYTE, the bit read at IN_0 is inserted as least significant bit (lsb) as shown below. IN_7 is considered as most significant bit (msb). 1 Note The same bit allocation also applies to the corresponding standard function block. SAFEBITS_TO_SAFEWORD / BITS_TO_WORD Description: Summarizes 16 (SAFE)BOOL input variables to one (SAFE)WORD output variable. Bit valence: In the output WORD, the bit read at IN_0 is inserted as least significant bit (lsb) as shown below. IN_15 is considered as most significant bit (msb). 1 Note The same bit allocation also applies to the corresponding standard function block. SAFEBYTES_TO_SAFEWORD / BYTES_TO_WORD Description: Summarizes two (SAFE)BYTE input variables to one (SAFE)WORD output variable. Bit valence: In the output WORD, the BYTE read at IN_0 is inserted as least significant BYTE (lsb) as shown below. IN_1 is considered as most significant BYTE (msb). 1 Note The same bit allocation also applies to the corresponding standard function block. SAFEWORDS_TO_SAFEDWORD / WORDS_TO_DWORD Description: Summarizes two (SAFE)WORD input variables to one (SAFE)DWORD output variable. Bit valence: In the output DWORD, the WORD read at IN_0 is inserted as least significant WORD (lsw). IN_1 is inserted as most significant WORD (msw). 1 Note The same bit allocation also applies to the corresponding standard function block. Splitting function blocks: SAFEBYTE_TO_SAFEBITS / BYTE_TO_BITS Description: Splits one (SAFE)BYTE input variable to eight (SAFE)BOOL output variables. Bit valence: The least significant bit (lsb), i.e., bit 0 of the input BYTE, is applied to output OUT_0. The most significant bit (msb) of the input BYTE is output at OUT_7. 1 Note The same bit allocation also applies to the corresponding standard function block. SAFEWORD_TO_SAFEBITS / WORD_TO_BITS Description: Splits one (SAFE)WORD input variable to 16 (SAFE)BOOL output variables. Bit valence: The least significant bit (lsb), i.e., bit 0 of the input WORD, is applied to output OUT_0. The most significant bit (msb) of the input WORD is output at OUT_15. 1 Note The same bit allocation also applies to the corresponding standard function block. SAFEWORD_TO_SAFEBYTES / WORD_TO_BYTES Description: Splits one (SAFE)WORD input variable to two (SAFE)BYTE output variables. Bit valence: Bits 0 to 7 of the input WORD are output as BYTE variable at OUT_0. Bits 8 to 15 of the input WORD are output as BYTE variable at OUT_1. 1 Note The same bit allocation also applies to the corresponding standard function block. SAFEDWORD_TO_SAFEWORDS / DWORD_TO_WORDS Description: Splits one (SAFE)DWORD input variable to two (SAFE)WORD output variables. Bit valence: Bits 0 to 15 of the input DWORD are output as WORD variable at OUT_0. Bits 16 to 31 of the input DWORD are output as WORD variable at OUT_1. 1 Note The same bit allocation also applies to the corresponding standard function block.