IBM System/7 Functional Characteristics - All about the IBM 1130 ...

Store Index (PSTX)0 5 8 15Op code0 1 1 0 1I IllXXXDisplacement6 8-F X XThe contents of the index register (R) replace the contents of the storage locationspecified by the effective address. The index register contents are not changed. IfR=000, the storage location contents are replaced by 0's.The effective address of the storage location is always generated using the IAR asthe base register.The carry and overflow indicators are not changed. The result indicators are changedto reflect the final contents of the storage location.Example:PSTX instruction (assumed to be at storagelocation 61)IAR during execution of PSTX instruction(contains address of next instruction atstorage location 62)0 8 15 0 15Op codeRDisplacement0 1 1 0 1 0 0 0 0 0 0 011 1 11 0 0 0 0 0 0 0 0 0 0 1 1 1 1 1 01 I 1 I1 11 1 1 11 1 1 111111111111111••■•••■,,,••••■•■■ ‘••111....,,•■•••,6 8-F 0 0 0 3 EEffective address generationIAR 00001.0000i0011;1110 Decimal 62Displacement (expanded to 16 bits) +000010000:000011111 Decimal 15Effective address of storage location 0000100001010011101 Decimal 770 15Storage location 77 before PSTXoperationXXXXXXXXXXXXXXXX1111111111 I 1111S■1111.N.,..1111., •••••••••,,,■1111.,X X X X0 15Storage location 77 after PSTXoperation0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 01111111111111110 0 0 0Processor Instructions 4-13