TS87C54X2 Temic Semiconductors, TS87C54X2 Datasheet - Page 10

• Manufacturer Part Number: TS87C54X2
• Description: 8-bit CMOS Microcontroller 0-60 MHz
• Manufacturer: Temic Semiconductors

TS80C54X2/C58X2
TS87C54X2/C58X2
6.2 Dual Data Pointer Register Ddptr
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 5.) that allows the program code to switch between them (Refer to Figure
3.).
External Data Memory
7
0
DPS
DPTR1
DPTR0
AUXR1(A2H)
DPH(83H) DPL(82H)
Figure 3. Use of Dual Pointer
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Rev. B - Aug. 31, 1999