IDL | PCON.0 | . |
PD | PCON.1 | . |
GF0 | PCON.2 | |
GF1 | PCON.3 | |
PCON.4 | ||
PCON.5 | ||
PCON.6 | ||
SMOD | PCON.7 | . SMOD = 1 2 , SMOD = 0 |
. 1. 1 PD IDL PD .
2. 0XXX0000B.
2 1/32 1/64 SMOD PCON:
BR2 = (2SMOD / 64) fosc, (2.3)
: BR2 2, ;
SMOD SMOD PCON;
fosc , .
2.12.7. 3 . 2 , /, (2.2).
2.12.8. 1 3 1 . 1 1, .. 0, 1 2
(. 2.11.) 2 . TMOD (.
. 2.7) 0010, .
BR1 = BR3 = 2SMOD fosc / {384 [256 (TH1)]}, (2.4)
: BR1 1, ;
BR3 3, ;
SMOD SMOD PCON;
fosc , ;
(TH1) 1.
1 1 3 . 2.11.
2.11
1
1 3
Baud Rate, | fosc, | SMOD | C/T | M1 | M0 | TH1 |
0FFH | ||||||
11,059 | 0FFH | |||||
11,059 | 0FFH | |||||
11,059 | 0FEH | |||||
11,059 | 0FDH | |||||
11,059 | 0FDH | |||||
11,059 | 0FAH | |||||
11,059 | 0FAH | |||||
11,059 | 0F4H | |||||
11,059 | 0E8H |
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2.13.1. (PC Program Counter), , [ 1 ].
2.13.2. - . 2.13. , , , , 0000H. (. . 2.9.4). , , , , , .
2.13.3. , , (. . 2.4), : , .
(LJMP, AJMP SJMP) , . 8051 (. 3.2) JMP. (. 3.3) JMP LJMP, AJMP SJMP.
- , , , , . , , 1 ( DJNZ).
. 2.13.
2.13.4. , 03, (. 2.16), 00 .
2.14.1. (stack) , LIFO (last-in, first-out) , . . , , . , .
2.14.2. . , , , .. . , , (- ), . - . , - , . - (.. , ) . . - , , . , .
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2.14.3. 8051 , - SP (Stack Pointer). ( RST) SP 07H. .
: PUSH ( ) POP ( ).
PUSH addr SP, , addr, (SP). POP addr : (SP) addr, SP.
(. 2.15) (. 2.16).
2.15.1. (subroutine) , , [ 3 ].
, ( ). , .
2.15.2. MCS-51 (. . 2.4) LCALL ( ) ACALL ( 2 ). :
1) PC 3,
2) - SP,
3) ,
4) - ,
5) ,
6) 16- (LCALL) 11- (ACALL) ( ).
2.15.3. RET (return), ( , ), , .
2.15.4. , .. . , .
2.15.5. - , , ( ), ( ).
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2.15.6. :
1) ,
2) ,
3) ,
4) .
2.16.1. (interrupt) , , .
( external interrupt) - , , ( internal interrupt). (hardware interrupt), , (software interrupt), .
, , . , ( ), .
2.16.2. 8051 , ( ) ( ). INT0 INT1 , 0, 1, .
8051 , (IC interrupt controller).
.
, , , 0003. 8 . () , , . 8051 . 2.12.
2.12