Intel MCS 51 User Manual page 274

intd.
83C152 HARDWARE DESCRIPTION
Byte
Address
080H
088H
090H
098H
OAOH
OA8H
OBOH
OB8H
OCOH
OC6H
ODOH
OD8H
OEOH
OE8H
OFOH
OF8H
SYMBOUCNAMEBITMAP
(MSB) (LSB)
PO.7 PO.6 PO.5 PO.4 PO.3 PO.2
Po.1 Po.o (Po)
TF1
.TR1 TFO TRO
IE1 ITI IEO
ITO
(TCON)
P1.7 I P1.6 I P1.5 I P1.4 I P1.3 I P1.2 I P1.1 I P1.O I (Pi)
SMO I SM1 I SM2 I REN I TB8 I RB8 I TI I RI I (SCON)
P2.7
P2.6 P2.5
P2.4 P2.3 P2.2 P2.1 P2.O (P2)
EA — — ES ETl EX1 ETo EXO
(IE)
P3.7 P3.6 P3.5 P3.4 P3.3 P3.2 P3.1 P3.O (P3)
— — —
Ps PT1 Pxl
PTO
Pxo
(1P)
P4.7 I P4.6 I P4.5 I P4.4 I P4.3 ! P4.2 I P4.1 I P4,0
— —
I EGSTE ] EDMA1 I EGSTV ] EDMAO I EGSRE I EGSRV
CY I AC FO
I
RS1 RSO Ov I — P
LNI I NOACK I UR I TCDT I TDN I TFNF I TEN I DMA
OVRI RCABTI AE I CRCE I RDN I RFNE I GREN I HABEN
(P4)
(IEN1)
(Psw)
(TSTAT)
(A)
(RSTAT)
(B)
— —
PGSTE
PDMA1 PGSTV PDMAO PGSRE PGSRV (IPN1)
Figure 2.3C. Bit Addresses
2.1.3
PROGRAM MEMORY
The
83C152
contains SK of ROM program memory,
and the 80C152uses only external program memory.
Figure 2.4 shows the program memorylocations and
where they reside. The user is alloweda maximum of
64K of program memory. In the 83C152 program
memoryfetchesbeyond 8K automaticallyaccessexter-
nal programmemory.Whenprogrammemoryis exter-
nally addr- all of the Port 2 pinsemit the address.
Since all of Port 2 is affectedby the address, unused
addresspinscannot be usedas normalI/O ports evenif
less than 64K of memoryis beingaccessed.
EXTERNAL
EXTERNAL IF~= O
INTERNAL IF~= 1
FFFFH
1FFFH
OOOOH
270427-4
Figure 2.4. Program Memory
7-1o