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6‹/#f P.60$ $!(O$PO7"[)N(25)"<R-kY)H9

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1.5.2. Sơ đồ khối và chức năng các khối
Hình 1. 4. Sơ đồ khối vi điều khiển PIC16F877A.
R#H5 _O1$>-B4^Q::n)_/7O1$C
{ T1$…<$"/e"$)$$"
{ T1$K,c*25)"<R…^H-<)</e/<f
{ T1$K,c*\$8(X-Ul…"X-Ul
{ T1$K,c™$e")$U…U™$eUe)$H"e<
{ T1$)$9$/ƒ80# $!(O$P…BH"<("$ee"<

{ T1$")$ bK$8"
{ T1$).$0$"$/e<
{ T1$)$"$J61$"$J6
{ T1$(fP M$"‚$8("25)"H)H1{
{ T1$76<"d(;"]6
0)U5]^/!(_'7^
Hình 1.5. Sơ đồ chân và chức năng các chân
• `lV|Tq+rC)‰0#OJ"1$0c$ ,)".b)‰0#
]d()O"sK')#$
• `lV%|T%qrC)‰< ,)".b)‰<;6d()O
• ` qrg%*a)
{ C)‰0#<eHe""‚u/*";6
{ 66C)‰0#] $876]6"<RO$]6"<R-B
• `UZ|Zq%rnU|q+rnU%|%q+rCg%*a)
{UZnn%Cd(;"|]6H1
{Znn%C)‰0#"25)">O'"*Znn%
• `U%|%|UX^{|UX^ŸqrCd(;"]6H1|)‰0#"25)">O'
"*%|‰0# $876(‹";6>K,|)‰0# $876‹>K,

• `U+|+|UX^ŸqrCd(;"]6H1|)‰0#"25)"O'+|)‰0#

• `UX%|  |:qZrCd(;";6H1|`& $!(O$P6<"H)
H)|)‰0#"25)"O'"*:
• `qn+%r0#VVq%n+rC#7`)(_>-B
0+`"P.>/""&O"P,B4[\::
`f#0$ $!(O$P"(,-B4^ddd0c$"]68)_/+8g ,#$K$"
˜$8 !( 23""$"<)/,"(ORd()OD1 ,." ,)"1$ 
6•6#%Z•0c$/,"(OR8#%ZZHk,c25)"<RQTdK$"nK,c
\$8(+4QdQKf"eU0#K,c\$8(XX-Ul0c$()23)%4dQKf"eV1
-lUDB|l#0c$++6$B|lgQO'(fP M$|
 7 b"‚).$0$K)_/7O1$*a)H(C
{ D$/e<ZCK, J/QK$"0c$K,$"GH1QK$"
{ D$/e<CK, J/4K$"0c$K,$"GH1ng"P"$8*a) J/
0#d()O).$0$)fO$0$ $!(O$P." ,)uJ ,
Hee6
4
{ D$/e<%CK, J/QK$"0c$K,$"GH1nK,6H"e<
{ $K,6"(<e|HH7| $!(J ,<[)d()
{ 7(‹)$"$J61$"$J6VV-qVf<(HVe<$-<"rnV-B0#B%
{ (‹)$"$J61$"$J6VUD0c$WK$" Lp
{ M))$"$J6H)H)-V-q-<eV0e-<"r0c$7` $!(O$P
Un~Un
 k'. g#/,"0#$ b"‚O7>0$ $!(O$P2C
{ k,c™H0c$O9a))$dg 23ZZZZZG
{ k,cXX-Ul0c$O9a))$dg 23ZZZZZZG
{ \$8(K,cXX-Ulg"P2("<\"<'Za/
{ T9a)".625)"<R0c$H $!(O$P>6G/!/
{ .6  23  25)  "<R  )f  "<'  /.  $8  BV-  qB  $<($"  Ve<$
-<)<//$)r"[)N(%`
{ ~")D$/e<0c$K, ,)"<)
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cH"O0#O[) 23 LpgKu$
K, J/25) "<R k, cH"O H•
23 !]6&"P"<)6GH(
R4k,c25)"<R
-B4^Q::
%k,c\$8(
k,c\$8(>-B#K,cXX-Ul 23$<#/$!(KO1$0c$
-B4^Q::K,c\$8( 23$<#/KO˜$KOg()23)%Q
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\$8()$=6"(]"$8"<)N(7"<R"<(fd(;"0##/)$9/Kc"8>25)
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Hình 1.7. Sơ đồ bộ nhớ dữ liệu PIC16F877A
D)$*a) bK$8"V^U
 `f#7")$ 23HI&)Ku$-b 23}) P"$J"]60# $!(
O$P7O1$*a) 23"‚36K'"<)0$ $!(O$Pg"P6`")$
V^U#/$$C")$V^U$'N( J7*a)K'"<)q-r0#
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