Systems Reference Library - All about the IBM 1130 Computing ...

COMPARE (CMP)FORMATS0 OP F T Disp 150 OP1 110111110 01 1 11111 111B 0-3 X XDESCRIPTIONThe contents of the accumulator (A) are comparedalgebraically against the contents of the core-storagelocation specified by the effective address (EA) of theinstruction. The contents of A and core storage remainunchanged. The instruction (I) register, which containsthe next sequential instruction address, is modifiedaccording to the results of the comparison as follows:If A is more positive than contents of EA, then 1=I andno skip occurs.If A is less positive than contents of EA, then 1=1+1 andone core-storage word is skipped.If A is equal to contents of EA, then 1=1+2, and twocore storage words are skipped.THE CARRY INDICATOR may be altered by thisinstruction, but has no significance.THE OVERFLOW INDICATOR is not changed by thisinstruction.EXAMPLESAssembler Language CodingEquivalent Machine Language InstructionLabel21 25Operation27 30F T323335 40SeeNoteHexadecimalValueDescriptionFormat1 1 , C,M,P, D,I,SIP, 1 BOXX Compare A with contents of CSL at EA (I + DISP)1 t 1 CIMIP 1 I D1I1S,P1,B 1XX Corn are A with contents of CSL at EA . 1 +ii •i i 1 CIMIP, 2 D,I,,P, S, 1B2XX Compare A with contents of CSL at EA (XR2+DISP)1 1 1 CAR I 3 D,I,S,P, , 1 B3XX Compare A with contents of CSL at EA (XR3+DISP)1 I 1 CM,P, L A,D,D,R, , I B400XXXX Compare A with contents of CSL at EA (Addr) LongShortInstruction1 1 1 CIM,P1 L I A,D,D,R, , 1 B500XXXX Compare A with contents of CSL at EA (Addr+XR1)Instructioni 1 / C IMIP / L 2 A,D,D,R, 1 1 B600XXXX Compare A with contents of CSL at EA (Addr+XR2)DirectC,M,P,Addressing3 A,D,D,R, 1 1 B70030001 Compare A with contents of CSL at EA (Addr+XR3)1 1 1 CIM,P1 L A,D.D,R,1B480XXXX Compare A with contents of CSL at EA (V in CSL at Adds) LongI 1 I C,M1P, I I A,D,D,R,,13580XXXX _ Compare A with contents of CSL at EA (V in CSL at Instructioni j I 1 1 1I I I I1 1"Addr+)(12 1")Indirect1 , 1 C,M,P, I 2 A,D,D,R, I 1 B680XXXX Compare A with contents of CSL at EA (V in CSL atAddressingi I 1 1 1 1 1 1 1 1 1 1 1 1 "Addr+XR2")1 / 1 CIMIP 1 I 3 A,D,D,R, I I B780XXXX Compare A with contents of CSL at EA (yin CSL at1 1 1 1 1 1 1 1 1 i 1 1 1 1 "Addr+XR3'')SitalleeetatieMEIX=22 X__ _48CMP