Chapter 3 Cpu Architecture; Memory Space - NEC 78K0/KD1 Series User Manual

3.1 Memory Space

Products in the 78K0/KD1 Series can each access a 64 KB memory space. Figures 3-1 to 3-5 show the memory
maps.
Caution Regardless of the internal memory capacity, the initial value of the internal memory size
switching register (IMS) of all products in the 78K0/KD1 Series is fixed (IMS = CFH). Therefore,
set the value corresponding to each product as indicated below.
Table 3-1. Set Values of Internal Memory Size Switching Register (IMS)
µ PD780121
µ PD780122
µ PD780123
µ PD780124
µ PD78F0124
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CHAPTER 3 CPU ARCHITECTURE

Internal Memory Size Switching Register (IMS)
42H
44H
C6H
C8H
Value corresponding to mask ROM version
Preliminary User's Manual U16315EJ1V0UD