© 2007 Pearson Education, Inc., Upper Saddle River, NJ. All rights reserved. This publication is protected by Copyright and written permission should be obtained from the publisher prior to any prohibited reproduction, storage in a retrieval system, or transmission in any form or by any means, electronic, mechanical, photocopying, recording, or likewise. For information regarding permission(s), write to: Rights and Permissions Department, Pearson Education, Inc., Upper Saddle River, NJ 07458. 293 www.Mohandesyar.com Name 0 40 80 120 clock rst En Ld Clr_P1_P0 Ld_P1_P0 Ld_R0 state[3:0] Data[7:0] P1[7:0] P0[7:0] R0[15:0] x 1 xx 2 4 8 2 a5 xx 8 1 ff a5 xx 4 ff a5 xxxx 00 ff a5a5 Digital Design – Solution Manual. M. Mano. M.D. Ciletti, Copyright 2007, All rights reserved. www.Mohandesyar.com 00 ffff © 2007 Pearson Education, Inc., Upper Saddle River, NJ. All rights reserved. This publication is protected by Copyright and written permission should be obtained from the publisher prior to any prohibited reproduction, storage in a retrieval system, or transmission in any form or by any means, electronic, mechanical, photocopying, recording, or likewise. For information regarding permission(s), write to: Rights and Permissions Department, Pearson Education, Inc., Upper Saddle River, NJ 07458. 294 www.Mohandesyar.com CHAPTER 9 9.1 (a) Asynchronous circutis do not use clock pulses and change state in response to input changes. Synchronous circuits use clock pulses and a change of state occurs in reponse to the clock transition. (b) The input signals change one at a time when the circuit is stable. (c) The circuit is in a stable state when the excitation variables (Y) are equal to the secondary variables (y) (see F. 9.1). Unstable otherwise. (d) The total state is the combination of binary values of the internal state and the inputs. Y1 = x1'x2 + y1x2 9.2 y1y2 Y2 = x1y2 + x2 y1 x1x2 00 01 11 10 00 00 11 01 00 01 00 11 01 01 x1x2 : 00, 10, 11, 01, 11, 10, 00 x2 11 00 11 11 01 10 00 11 11 00 y1y2 : 00, 00, 01, 11, 11, 01, 00 x1 y2 9.3 (a) x1 Y = x1x' 2 + (x1 + x'2)y x2 z=y y (b) y y x1 x1x2 00 01 11 10 0 0 0 0 1 1 1 0 1 1 y y x1 x1x2 00 01 11 10 0 0 0 0 0 1 1 1 1 1 x2 x2 (c) Digital Design – Solution Manual. M. Mano. M.D. Ciletti, Copyright 2007, All rights reserved. www.Mohandesyar.com
