Chapter 16AppendixXVI - 66 Extension Instruction SpecificationMCST48 (48-bit saturation instruction for multiply and accumulate result)[Instruction format (macro name)]MCST48 Dn, Dn[Assembler mnemonic]udf06 Dn, Dn[Operation]This instruction stores the 48-bit signed positive maximum value (0x00007fffffffffffff ) and the negativemaximum value (0xffff 800000000000) in Dn respectively when the 64-bit multiply and accumulate result, storedin the multiply and accumulate registers MCRH and MCRL, is equal to or greater than the 48-bit positivemaximum value (0x00007fffffffffff ) and equal to or smaller than the negative maximum value(0xffff800000000000). In any other case, the instruction outputs the contents of MCRH and MCRL and stores thevalues of bit 47 to bit 16 of this output in Dn.Additionally, the instruction places the content of the multiply andaccumulate overflow detection flag register MCVF in the V flag.[Flag changes]When multiply and accumulate overflow is not detected (MCVF = 0 )When multiply and accumulate overflow is detected (MCVF = 1 )[Note for programming]Updating of the PSW as a result of flag changes is delayed by 1 instruction.Note, however, that flags can be evaluated for the Bcc and Lcc instructions before flag changes are reflected in thePSW.Flag Change ConditionV 0 Indicates that multiply and accumulate operation is valid.C 0 Always "0".N * UndefinedZ * UndefinedFlag Change ConditionV 1 Indicates that multiply and accumulate operation is invalid.C 0 Always "0".N * UndefinedZ * Undefined
