TS80C54X2XXX-MCE ATMEL Corporation, TS80C54X2XXX-MCE Datasheet - Page 11

• Manufacturer Part Number: TS80C54X2XXX-MCE
• Description: At87c54x2, Ts87c54x2
• Manufacturer: ATMEL Corporation

7. Dual Data Pointer Register Ddptr
4431E–8051–04/06
7
AUXR1(A2H)
The additional data pointer can be used to speed up code execution and reduce code size in a
number of ways.
The dual DPTR structure is a way by which the chip will specify the address of an external data
memory location. There are two 16-bit DPTR registers that address the external memory, and a
single bit called
DPS = AUXR1/bit0 (See Table 7-1.) that allows the program code to switch between them
(Refer to Figure 7-1).
Figure 7-1.
DPS
0
Use of Dual Pointer
DPH(83H) DPL(82H)
DPTR1
DPTR0
External Data Memory
AT/TS8xC54/8X2
11