IBM 610 Manual Of Operation

Also see for 610: Technical overview and introduction

10 BM 6 10CHANGING THE SIGN Example:01 CPY OJ(cNn (Convert)It is sometimes necessary, during a calculation, tochange the sign of a number from plus to minus orvice-versa. On most computers this necessitates find-ing a register containing all zeros and subtracting thenumber from the zero register.However, in the IBM 610 it is necessary only togive a single command—convert.The depression of this key tells the machine to re-place the contents of the selected register by the nega-tive of the original contents. The register remainsselected.Example 1:06 CNVRegisterBefore 06+000000000000013 .6J00000000000000After 06-000000000000013 .650000000000000006 Remains Selected17 CNV.0700000000000000.0700000000000000Example 2:Before 17 - 000000000000003After 17-J-OOOO00O0O00000317 Remains SelectedCLEARINGTransfer of Data within the MachineCOPY) (Copy)In order to move a number from a storage registerto another location in storage we use copy.The depression of this key tells the machine to erasethe contents of the selected register, to replace it byaill zeros with a plus sign, and then add the contentsof fekc next addressed register to the zeros of the se-lected regi«ter. The contents of the addressed registerFcmain unchanged. The selected register remains se-lected.One important use of this instruction is for thestorage of intermediate results during calculation.RegisterBefore 01+000000000000001 .730000000000000005 + 000000000000002 .6700000000000000After 01+000000000000002 .670000000000000005-f-000000000000002 .670000000000000001 SelectedSetting a Register to Zero(Clear)In order to clear a storage location previous to anaccumulation we use clear.The depression of this key tells the machine to erasethe contents of the selected register and replace theoriginal contents with all zeros and a plus sign.Example:22 CLRRegisterBefore 22+000021563185733 .4210000000000000After 22+000000000000000 .000000000000000022 SelectedClear Right Half^CLR^JH. (Clear Right Half)The depression of this key causes the last sixteenpositions of the selected register to be replaced byzeros. The machine takes no cognizance of decimalposition or the contents of the right half of the regis-ter. The selected register remains selected. The decimalpoint is not erased.Example:29 CLR RHRegisterBefore 29+000000000001765 .4180021004000000After 29+000000000001765 .000000000000000029 SelectedSHIFTINGIf the operator wishes to shift the contents of a reg-ister to the left or to the right, he has four operationsavailable to help him accomplish this. As a result ofshifting, the sign position never changes, but numbersshifted beyond register limits are lost.