Figure 3.8.1A Mode Data Structure; Table 3.8.1A Mode Pin Setting - Fujitsu F2MC-8L MB89620 Series Hardware Manual

3.8 Memory Access Modes
3.8.1 Selecting Memory Access Mode
The mode pins (MOD0, MOD1) and mode data select the memory access mode.
Some products support single-chip mode only.
n Mode Pins (MOD0, MOD1)
The pins relating to the external bus mode are initialized based on the mode pin (MOD0, MOD1)
settings when a reset source occurs. The mode pin settings determine whether the mode data
and reset vector are read from internal or external ROM during the reset operation.
Do not change the mode pin settings, even after completion of the reset (i.e. during normal
operation).
Table 3.8.1a lists the mode pin settings.

Table 3.8.1a Mode Pin Setting

Pin state
MOD1
V
SS
V
SS
V
CC
V
CC
n Mode Data
The device reads the mode data from the location specified by the mode pins (MOD0, MOD1)
and selects single-chip mode or external bus mode (external ROM mode or internal ROM/
external bus mode).
Figure 3.8.1a shows the structure of the mode data.
Check: When selecting external ROM mode, always specify external bus mode for the mode data.
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CHAPTER 3 CPU
MOD0
Reads the mode data and reset vector from internal ROM.
V Selects single-chip mode or internal ROM/external bus mode, depending on the content of the
SS
mode data.
Reads the mode data and reset vector from external ROM. As the device is now in external
V
CC
ROM mode, always specify external bus mode ("01
V Prohibited setting
SS
V Prohibited setting
CC
Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
Address
FFFD
H

Figure 3.8.1a Mode Data Structure

Set the mode pins and mode data for single-chip mode on products that support single-chip mode
only.
Description
Data Operation
00 Selects single-chip mode.
H
01 Selects external bus mode.
H
Other Reserved. Do not set this value.
") in the mode data.
H
MB89620 series