AT89C2051 View Datasheet(PDF) - Atmel Corporation

Part Name

Description

Manufacturer

AT89C2051

8-bit Microcontroller with 2K Bytes Flash

Atmel Corporation 

AT89C2051

6. Special Function Registers

A map of the on-chip memory area called the Special Function Register (SFR) space is shown in

the table below.

Note that not all of the addresses are occupied, and unoccupied addresses may not be imple-

mented on the chip. Read accesses to these addresses will in general return random data, and

write accesses will have an indeterminate effect.

User software should not write 1s to these unlisted locations, since they may be used in future

products to invoke new features. In that case, the reset or inactive values of the new bits will

always be 0.

Table 6-1. AT89C2051 SFR Map and Reset Values

0F8H

0F0H

B

00000000

0E8H

0E0H

ACC

00000000

0D8H

0D0H

0C8H

PSW

00000000

0C0H

0B8H

0B0H

0A8H

0A0H

IP

XXX00000

P3

11111111

IE

0XX00000

98H

SCON

00000000

90H

P1

11111111

88H

TCON

00000000

80H

SBUF

XXXXXXXX

TMOD

00000000

SP

00000111

TL0

00000000

DPL

00000000

TL1

00000000

DPH

00000000

TH0

00000000

TH1

00000000

0FFH

0F7H

0EFH

0E7H

0DFH

0D7H

0CFH

0C7H

0BFH

0B7H

0AFH

0A7H

9FH

97H

8FH

PCON

0XXX0000

87H

5

0368G–MICRO–6/05

Share Link: