1.9) Tr s BCDB 9 ca mt s thp phn: c xc nh bng cch ly 9 tr cho tng ch s thp phn. V d: B 9 ca 37 = 99 37 = 62 B 9 ca 419 = 999 419 = 580

Tr 2 s BCD (A B) c thc hin theo quy tc nh sau: (i) (ii) (iii) (iv) A + [b 9 ca B] Nu decade no > 9, th hiu nh bng cch cng 0110b. Nu c nh decade c trng s cao nht, th kt qu l s dng cng bit nh vo kt qu c kt qu sau cng. Nu khng c nh decade c trng s cao nht, th kt qu l s m ly b 9 c kt qu sau cng.

V d: Thc hin php tr 2 s BCD8d -3d 5d 8 +6 1000 + 0110 1110 0110 1 0100 1 0101 QT (i) QT (ii) QT (iii) 5d

75d -49d 26d

75 +50

0111 +0101 1100 0110 1 0010

0101 0000 0101 .... 0101 1 0010 0110

QT (i) QT (ii) QT (iii) 26d

86d -38d 48d

86 +61

1000 +0110 1110 0110 1 0100

0110 0001 0111 .... 0111 1 0100 1000

QT (i) QT (ii) QT (iii) 48d

28d -57d -29d

28 +42

0010 1000 +0100 0010 0110 1011 0110 0111 0001 B-9 (71)

QT (i) QT (ii) QT (iv) -29d

39d -87d -48d

39 +12

0011 1001 +0001 0010 0100 1011 0110 0101 0001 B-9 (51)

QT (i) QT (ii) QT (iv) -48d

35d -67d -32d

35 +32

0011 +0011 0110 B-9

0101 0010 0111 (67)

QT (i) -32d