AT89C51RB2-RLTCM ATMEL [ATMEL Corporation], AT89C51RB2-RLTCM Datasheet - Page 18

• Manufacturer Part Number: AT89C51RB2-RLTCM
• Description: 8-bit Microcontroller with 16K/ 32K Bytes Flash
• Manufacturer: ATMEL [ATMEL Corporation]

Dual Data Pointer
Register (DPTR)
Figure 6. Use of Dual Pointer
18
AT89C51RB2/RC2
7
AUXR1(A2H)
DPS
0
The additional data pointer can be used to speed up code execution and reduce code
size.
The dual DPTR structure is a way by which the chip will specify the address of an exter-
nal data memory location. There are two 16-bit DPTR registers that address the external
memory, and a single bit called DPS = AUXR1.0 (see Table 17) that allows the program
code to switch between them (see Figure 6).
DPH(83H) DPL(82H)
DPTR1
DPTR0
External Data Memory
4180B–8051–04/03