SAB-C509-LM SIEMENS [Siemens Semiconductor Group], SAB-C509-LM Datasheet - Page 27

• Manufacturer Part Number: SAB-C509-LM
• Description: 8-Bit CMOS Microcontroller
• Manufacturer: SIEMENS [Siemens Semiconductor Group]

C509-L
Multiple Datapointers
As a functional enhancement to the standard 8051 architecture, the C509-L contains eight 16-bit
datapointers instead of only one datapointer. The instruction set uses just one of these datapointers
at a time. The selection of the actual datapointer is done in the special function regsiter DPSEL.
Figure 14 illustrates the datapointer addressing mechanism.
Figure 14
External Data Memory Addressing using Multiple Datapointers
Semiconductor Group
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