C501_1 Datasheet, PDF (24/121 Pages) Siemens Semiconductor Group – 8-Bit Single-Chip Microcontroller

Memory Organization
C501
3.4 Special Function Registers
All registers, except the program counter and the four general purpose register banks, reside in the
special function register area.
The 27 special function register (SFR) include pointers and registers that provide an interface
between the CPU and the other on-chip peripherals. There are also 128 directly addressable bits
within the SFR area.
All SFRs are listed in table 3-1 and table 3-2.
In table 3-2 they are organized in groups which refer to the functional blocks of the C501. Table 3-3
illustrates the contents (bits) of the SFRs.
Semiconductor Group
3-3