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

Read IAR Backup (RIB) (5010 Processor Module Model E only)0 15Op code R Level Mod11111 XXX 00 XX 11011111 II 111 111F 8-F 0-3The contents of the instruction address register backup for the selected level replace thecontents of the register on the current level, specified by the R field, or the accumulator ifR = 000. The level is selected by the binary encoded value in bits 8 through 11 of theinstruction. Since level 0 has no instruction address register backup, this instructionresults in the specified register having a 0 value if level 0 is selected. The carry, overflow,and result indicators on the selected level are not changed. The result indicators on thecurrent level are changed depending on the contents stored in the specified register.Example:0 15RIB instructionOp code R Level Mod1 1 1 1 1 1 1 0 0 0 1 0 1 1 0 11111 II 111 IIIF E2IAR backup registerIndex register 6 Level 20 15 0 15RIB instructionis fetched1 1 1 1 1 1 1 1 1 1 1 1 1 I I(Decimal 88)0 0 0 010 0 0 010 1 0 111 0 0 0111111111111111XX X X0 0 5 80150 15After R I Binstructionexecution(Decimal 88)0 1 0 1 0 1 01 01010 1_010 1110 1111 10101 0(Decimal 88)0 0 0 010 0 0 010 1 0 1 1 1 0 0 0111111111111111■••••••■,,,■••••, ,.••••••„,•■•■••,,•■••••••,...........\■■••■••'0 0 5 8 0 0 5 8Processor Instructions 4-47