Slide Ch01 Thiet Ke May Trang Thai

Chng 1 THIT K MY TRNG THI

1. GII THIU MY TRNG THIS khac biet gia mach to hp va mach tuan t.Mach tuan t con c goi la may trang thai hu han FSM (Finite State Machine) hay goi tat la may trang thai.Cac thanh phan cua mot FSM:Bo nh trang thaiMach logic trang thai ke tiepMach logic ngo raMay trang thai c chia lam hai mo hnh:Mo hnh Moore Mo hnh Mealy

1. GII THIU MY TRNG THI (tt)

Mo hnh MealyHnh 1.1 Cac mo hnh may trang thai

1. GII THIU MY TRNG THI (tt)

Mo hnh MooreHnh 1.1 Cac mo hnh may trang thai

1. GII THIU MY TRNG THI (tt)May trang thai lu lai moi trang thai trong mot khoang c goi la thi gian trang thai (state time)

Thi gian trang thai = Thi gian chuyen bien + Thi gian on nh

Hnh 1.2 Bieu o thi gian cua may trang thai

2.bin

1. GII THIU MY TRNG THI (tt)Cac phng trnh trong khoang thi gian on nh:W(iT) = g[X(iT), Y(iT)]Z(iT) = f [X(iT), Y(iT)](Mealy)Hay Z(iT) = f [Y(iT)](Moore)Ngo ra dang ng ong (pipelined outputs)

Hnh 1.3 May trang thai Mealy vi ngo ra dang ng ong

2. PHN TCH MY TRNG THICc bc phn tch:Xac nh cac phng trnh kch thch (excitation equations)Xac nh cac phng trnh chuyen tiep (transition equations) Xay dng bang chuyen tiep (transition table) Xac nh cac phng trnh ngo ra (output equations) Xay dng bang chuyen tiep/ngo ra.Xay dng bang trang thai/ngo ra.(Tuy chon) Ve gian o trang thai (state diagram/graph).

2. PHN TCH MY TRNG THI (tt)V d: Phan tch may trang thai sau:

Hnh 1.4 May trang thai ong bo dung D flip-flop kch canh len

2. PHN TCH MY TRNG THI (tt)Phng trnh kch thch:

Phng trnh ac tnh cua D-FF: Q+ = D

Bang chuyen tiep

2. PHN TCH MY TRNG THI (tt)Phng trnh ngo ra:

MAX = Q1.Q0.EN Bang trng thai/ngo ra:

2. PHN TCH MY TRNG THI (tt)Gian o trang thai:

Trng hp ngo ra kieu Moore:

2. PHN TCH MY TRNG THI (tt)Gian o trang thai kieu Moore:

Gian o thi gian:

Hnh 1.7 Gian o thi gian cho v du phan tch may trang thai

2. PHN TCH MY TRNG THI (tt)Bai tapPhan tch may trang thai ong bo c cho tren hnh P1.1. Viet cac phng trnh kch thch/ngo ra, bang chuyen tiep/ngo ra, bang trang thai/ngo ra va ve gian o trang thai (dung cac ten trang thai A-D cho Q1Q2= 00 - 11).

Hnh P1.1

3. THIT K MY TRNG THICc bc thit k:Xay dng gin o trang thai hay bang trang thai/ngo ra(Tuy chon) Toi thieu hoa so trang thaiGan (ma hoa) trang thaiXay dng bang chuyen tiep/ngo raXay dng bang kch thchDan ra cac phng trnh kch thch va ngo raThc hien mach

3.1. XY DNG GIN TRNG THIV du 1.2: Dan ra gian o trang thai cho mot mach phat hien chuoi co s o khoi nh tren hnh 1.9. Khi chuoi vao la 101 th Z=1, ngc lai Z=0.

Hnh 1.9 S o khoi cua mach phat hien chuoi v du 1.2

Hnh 1.12 Gian o Mealy cho v du 1.2

X

Clk

Z

S0

S1

0/0

1/0

S2

0/0

1/1

1/0

0/0

3.1. XY DNG GIN TRNG THI (tt)Bang trang thai

Trng hp may trang thai kieu Moore:

S00

0

S10

S20

1

0

S31

0

1

1

0

3.1. XY DNG GIN TRNG THI (tt)V du 1.3: Dan ra gian o trang thai cho mot mach phat hien chuoi co s o khoi nh tren hnh 1.9. Ngo ra Z = 1 neu chuoi ngo vao tan cung la 010 hay 1001, ngc lai Z = 0.

Hnh 1.18 Gian o Mealy hoan chnh cho v du 1.3

S0

S1

S2

S3

S4

S5

0/0

1/0

0/1

1/0

a

1/0

b

0/0

c

0/0

d

e

1/1

i

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1/0

g

0/0

f

1/0

h

Trang thai

Chuoi nhan c

S0

S1

S2

S3

Reset

0

01

010 hay 10

S4

S5

1

100

3.1. XY DNG GIN TRNG THI (tt)Bai tap:Dan ra gian o trang thai cho mot mach phat hien chuoi co s o khoi nh tren hnh. Ngo ra Z = 1 neu chuoi ngo vao tan cung la 0010 hay 100, ngc lai Z = 0. V du : X = 1 1 0 0 1 0 0 1 0 1 0 0 1 0 1 Z = 0 0 0 1 0 1 1 0 1 0 0 1 0 1 0 Chu y la mach se khong reset ve trang thai ban au khi xay ra Z = 1.Gi y: li giai toi thieu can 6 trang thai.

X

Clk

Z

3.2. RT GN BNG TRNG THITi sao nn rt gn bng trng thi?S FF cn l t nht.S trng thi t nht c th tn dng c nhiu dont care hn gim s cng cn ci t.nh ngha: Hai trang thai Si va Sj c goi la tng ng nhau neu va ch neu:ng vi moi to hp ngo vao tac ong se cho cac ngo ra giong nhau.ng vi moi to hp ngo vao tac ong se tao ra cap trang thai ke tiep tng ng nhau.Gii thiu cac qui trnh rut gon trang thai:Tm hang tng ng (row matching)Phan nhom tng ng (equivalence partitioning)Bang keo theo (implication table/chart)

3.2. RT GN BNG TRNG THI (tt)3.2.1. Phng phap tm hang tng ng:V du 1.4: Dan ra gian o trang thai cho mot mach phat hien chuoi co s o khoi nh tren hnh 1.9. Ngo ra Z = 1 neu chuoi ngo vao tan cung la 1010 hay 0110, ngc lai Z = 0. Mach se reset sau moi 4-bit vao.V du ve ap ng vao-ra:

3.2.1. Phng phap tm hang tng ng: (tt)V du 1.4: (tt)Gian o trang thai:

3.2.1. Phng phap tm hang tng ng: (tt)V du 1.4: (tt) Bang trang thai/ngo ra ban au:

3.2.1. Phng phap tm hang tng ng: (tt)V du 1.4: (tt)

3.2.1. Phng phap tm hang tng ng: (tt)V du 1.4: Bang trang thai rut gon va gian o trang thai tng ng:

3.2.2. Phng phap phan nhom tng ng V du 1.5: Rut gon bang trang thai c cho tren hnh sau:

3.2.2. Phng phap phan nhom tng ng (tt)Phng phap phan nhom tng ng co the c tom tat nh sau:Bat au vi P0 cha tat ca cac trang thai cua mach trong mot nhom.Xac nh cac nhom cua P1 bang cach quan sat phan ngo ra cua bang trang thai/ngo ra va nhom cac trang thai vi cac gia tr ngo ra giong nhau vao chung mot nhom.Xac nh cac nhom cua Pi t Pi 1, i > 1:Xac nh cac trang thai ke tiep cua moi nhom trong Pi 1 ng vi moi to hp ngo vao.Neu chung nam trong cung mot nhom trong Pi 1 th khong tach nhom tng tng.Neu khong, tach nhom tng ng sao cho cac nhom c tach co cac trang thai ke tiep nam trong cung mot nhom cua Pi 1.Lap lai cho tat ca cac to hp ngo vao.Lap lai bc 3 cho en khi khong the tach nhom c na.

3.2.3. Phng phap dung bang keo theoBang keo theo cung cap mot cau truc e so sanh moi trang thai vi cac trang thai con lai trong bang trang thai e xac nh tnh tng ng cua chung.

3.2.3. Phng phap dung bang keo theo (tt)Noi dung trong moi o phu thuoc vao s tng ng cua cap trang thai toa o:(1) Dau X bieu th cap trang thai toa o cua o la khong tng ng;(2) Dau cho biet cap trang thai toa o cua o la tng ng khong ieu kien; (3) Cac cap trang thai ke tiep tng ng vi cac to hp ngo vao, bieu th s tng ng co ieu kien.

3.2.3. Phng phap dung bang keo theo (tt)V du 1.6: Rut gon bang trang thai c cho tren hnh cua vd 1.6:

3.2.3. Phng phap dung bang keo theo (tt)Phng phap dung bang keo theo co the tom tat nh sau:Ve bang keo theo va ien vao moi o vi dau X, dau hay cac cap trang thai ke tiep tuy thuoc vao cac cap trang thai toa o.Duyet qua bang t tren xuong di, t trai qua phai va anh dau X vao cac o neu co t nhat mot cap trang thai trong cac o o tng ng vi mot o a co dau X trong bang.Lap lai bc 2 cho en khi khong con o nao co the anh dau X na.Cac trang thai toa o tng ng vi cac o khong co dau X la tng ng.Ket hp cac cap trang thai tng ng at c bc 4, neu c, e tao thanh cac nhom tng ng ln hn bang cach dung ieu kien bac cau.Loai bo va thay the cac trang thai tng ng trong bang trang thai e at c bang trang thai rut gon.

3.2.3. Phng phap dung bang keo theo (tt)V du 1.7: Rut gon bang trang thai c cho tren hnh sau:

E F, E G, F G E F G

Bai tapRut gon bang trang thai sau:

3.3. GAN TRANG THAISo bien trang thai m c chon sao cho

vi n la so trang thai Gan trang thai la qua trnh phan phoi 1 trong to hp co the cua ma m-bit cho mot trong cac trang thai sao cho moi trang thai tng ng vi mot t ma m-bit duy nhat. Bang gan trang thai (state map): co mot o cho mot ma trang thai, e quan sat tnh ke can trong khi gan.V d 1.8: Phep gan trang thai cho gian o vi 5 trang thai:

3.3.1. Gan quy tch trang thai toi thieuS thay oi so bit t hn co the dan en toi thieu hoa viec tnh toan va tang o tin cay. Co gang at c quy tch toi u bang viec gan cac ma cach-1.

V du 1.9: Phep gan quy tch trang thai toi thieu cho gian o tren

3.3.2. Gan trang thai theo cac quy tac(1) Cac trang thai co cung trang thai ke tiep ng vi cung tac ong ngo vao nen c ma hoa ke can.(2) Cac trang thai la trang thai ke tiep cua cung mot trang thai nen c ma hoa ke can.(3) Cac trang thai co cung ngo ra ng vi cung tac ong ngo vao nen c ma hoa ke can.

3.3.2. Gan trang thai theo cac quy tac (tt)V du 1.10: Gan trang thai cho cac gian o sau:

S0 va S3 nen c gan ke can (qui tac 1).S1 va S5 nen c gan ke can (qui tac 2). S0, S1, S3 va S4 nen c gan ke can (qui tac 3).

3.3.2. Gan trang thai theo cac quy tac (tt)Mt s lu y khi ien vao bang: Nen gan trang thai khi au (trang thai reset) la 0 tren bang.Cac ieu kien ke can quy tac 1 va cac ieu kien ke can xuat hien nhieu lan nen c u tien thoa man trc.Khi can co nhieu trang thai ke can nhau th nen at cac trang thai nay trong nhom cac o ke can trong bang gan trang thai.Trng hp co 2 hay nhieu bien ngo ra th cung co the lay u tien ke can theo quy tac 3 cao hn (neu quan tam en rut gon cac ham ngo ra).

3.3.2. Gan trang thai theo cac quy tac (tt)V du 1.11: Gan trang thai cho bang trang thai sau:

3.3.2. Gan trang thai theo cac quy tac (tt)V du 1.11: (tt)Tap cac trang thai ke can rut ra theo quy tac 1 va 2: (S0, S1, S3, S5); (S3, S5); (S4, S6); (S0, S2, S4, S6)(S1, S2); (S2, S3); (S1, S4); (S2, S5)x2; (S1, S6)x2

Co the gan theo 1 trong 2 cach sau:

3.3.2. Gan trang thai theo cac quy tac (tt)V du 1.11: (tt)Gia s dung phep gan hnh a.

3.3.2. Gan trang thai theo cac quy tac (tt)V du 1.11: (tt)

1

x

1

1

x

1

1

1

1

1

1

00

01

11

10

BC

XA

00

01

x

0

0

0

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0

0

0

11

10

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1

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1

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11

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XA

00

01

x

0

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1

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1

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1

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01

11

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BC

XA

00

01

x

1

1

1

1

0

1

0

11

10

3.3.2. Gan trang thai theo cac quy tac (tt)V du 1.12: Gan trang thai cho bang trang thai sau:

3.3.2. Gan trang thai theo cac quy tac (tt)V du 1.12: (tt)Hai phep gan co the dung:Phep gan (a) khong thoa cac ke can (b,f), (c,e) va (e,f); phep gan (b) khong thoa cac ke can (d,f) va (e,f)

Bai tap1. Mot mach tuan t co mot ngo vao (X) va mot ngo ra (Z). Ve gian o trang thai Mealy cho moi trng hp sau:a) Ngo ra Z =1 neu tong so bit 1 nhan c chia het cho 3.b) Ngo ra Z =1 neu tong so bit 1 nhan c chia het cho 3 va tong so bit 0 nhan c la mot so chan ln hn 0. 2. Thiet ke mot mach tuan t ong bo kiem tra ngo vao X va tao ngo ra la Z = 1 khi phat hien chuoi ngo vao tan cung la 0101, vi ieu kien khong xay ra chuoi 110.V du : X = 0 1 0 1 0 1 1 0 1 0 1 Z = 0 0 0 1 0 1 0 0 0 0 0 Chu y la mach se khong reset ve trang thai ban au khi xay ra Z = 1.

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Slide Ch01 Thiet Ke May Trang Thai