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                     260                         Fundamentals of Computers                          NPP

                        Signed - 2's Complement Representation      gmBÝS> 2's H$m°påßb_|Q> à{V{Z{YËd … Bg_| ^r MSB
                    : In this representation also MSB is 1. Remaining  Ho$ ñWmZ na 1 hmoVm h¡ Omo F$U {MÝh Xem©Vm h¡ Ÿ& ~mH$s
                    bits are 2's Complement of the magnitude. For  H$s {~Q>| n[a_mU H$m 2's H$m°påßb_|Q>> Xem©Vr h¢ & O¡go,
                    example,  –12  can be represented as:
                                                                -12 H$mo Bg Vah go Xem©`m Om gH$Vm h¡ …


                                                             12

                                                 1         0100




                                           Sign Bit        1’s Complement of Magnitude
                        Thus –12 in this representation is 10100.   AWm©V² - 12 H$mo Bg_| Eogm {bIm Om gH$Vm h¡ …

                                                                10100
                        From  the  above  example  it  is  clear  that  CnamoŠV dU©Z  go  ñnï> hmoVm h¡ {H$ - 12 H$m
                    representation of -12 can be obtained from +12  à{V{Z{YËd +12 Ho$ à{V{Z{YËd go Bg àH$ma ^r {ZH$mb
                    with help of following procedure :
                                                                gH$Vo h¢ …
                    1.  Signed-Magnitude Representation-        1. (gmBÝS>-_op½ZQ²>`yS>)
                                             + 12                        – 12

                                             01100                       11100
                        Just complement sign bit.                   {g\©$ {MÝh dmbr {~Q> (MSB) H$m H$m°påßb_|Q> H$am|&
                    2.  Signed - 1's Complement Representation-  2. (gmBÝS>-  1's H$m°påßb_|Q>) gånyU© g§»`m H$m  1's
                        Complement all the bits including sign-bit :  H$m°påßb_|Q> boZo go + 12 go - 12 H$m à{V{Z{YËd
                                                                    àmá hmoVm h¡ Ÿ&
                                              + 12                      – 12

                                              01100                     10011
                    3.  Signed - 2's Complement Representation:  3. (gmBÝS> 2's H$m°påßb_|Q>>) gånyU© g§»`m {Og_| {MÝh
                        Take  2's  Complement  of  the  complete    dmbr {~Q> ^r em{_b h¡, H$m 2's H$m°påßb_|Q> boVo
                        number including sign bit                   h¢ Ÿ&

                                             + 12                        – 12

                                             01100                       10100

                    3.27  8-bit  representation  of  signed     3.27 gmBÝS> nyUmªH$m| H$m  bit _| à{V{Z{YËd
                    numbers
                        Consider  an  example  of  +12.  It  can  be
                    represented using 5-bits as follows:
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