C509-L_97 Datasheet, PDF (43/290 Pages) Siemens Semiconductor Group – 8-Bit CMOS Microcontroller

Memory Organization
C509-L
As long as bit RMAP is set, mapped special function registers can be accessed. This bit is not
cleared by hardware automatically. Thus, when non-mapped/mapped registers are to be accessed,
the bit RMAP must be cleared/set by software, respectively each.
There are also 128 directly addressable bits available within each SFR area (standard and mapped
SFR area). All SFRs with addresses where address bits 0-2 are 0 (e.g. 80H, 88H, 90H, 98H, …,
F8H, FFH) are bitaddressable.
The 103 special function register (SFR) include pointers and registers that provide an interface
between the CPU and the other on-chip peripherals. The SFRs of the C509-L are listed in table 3-4
and table 3-5. In table 3-4 they are organized in groups which refer to the functional blocks of the
C509-L. Table 3-5 illustrates the contents of the SFRs in numeric order of their addresses.
Semiconductor Group
3-18
1997-10-01