Table of Contents
Advertisement
21.1 Internal Memory Size Switching Register
The internal memory capacity can be selected using the internal memory size switching register (IMS).
IMS is set by an 8-bit memory manipulation instruction.
RESET input sets IMS to CFH.
Caution The initial value of IMS is "setting prohibited (CFH)". Be sure to set the value shown in Table 21-
2 for each product at initialization. When using the 78K0/KB1+ to evaluate the program of a mask
ROM version of the 78K0/KB1, be sure to set the values shown in Table 21-2.
Figure 21-1. Format of Internal Memory Size Switching Register (IMS)
Address: FFF0H
After reset: CFH
Symbol
7
IMS
RAM2
RAM2
0
0
ROM3
0
0
0
The IMS settings required to obtain the same memory map as mask ROM versions are shown in Table 21-2.
Table 21-2. Internal Memory Size Switching Register Settings
Flash Memory Version
(78K0/KB1+)
µ
PD78F0101H
µ
PD78F0102H
µ
PD78F0103H
334
CHAPTER 21 FLASH MEMORY
R/W
6
5
RAM1
RAM0
RAM1
RAM0
0
0
768 bytes
1
0
512 bytes
Other than above
Setting prohibited
ROM2
ROM1
0
1
1
0
1
1
Other than above
Target Mask ROM Version
(78K0/KB1)
µ
PD780101
µ
PD780102
µ
PD780103
Preliminary User's Manual U16846EJ1V0UD
4
3
2
0
ROM3
ROM2
Internal high-speed RAM capacity selection
ROM0
Internal ROM capacity selection
0
8 KB
0
16 KB
0
24 KB
Setting prohibited
Internal Memory Size
Switching Register (IMS)
42H
04H
06H
1
0
ROM1
ROM0
Advertisement
Table of Contents
