Mode Pins (Md2 To Md0) - Fujitsu MB90480 Series Hardware Manual

7.2

Mode Pins (MD2 to MD0)

Mode pins are three external pins (MD2 to MD0) that specify the reset vector and mode
data fetching method.
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Settings of mode pins (MD2 to MD0)
Mode pins (MD2 to MD0) are used to select the source, either the external or internal data bus
when reset vectors are read and stored, and to select the bus width when the external data bus
is used. For a device with built-in FLASH ROM, the mode pins are also used to set the FLASH
ROM write mode for writing built-in ROM program.
Table 7.2-1 lists the contents of mode pin settings.
Table 7.2-1 Contents of mode pin settings
P81 P80 MD2 MD1
- - 0
- - 0
- - 0
- - 0
- - 1
- - 1
1 0 1
- - 1
Note:
MD2 to MD0: Specify 0=V
default value of 8 bits. To specify 16 bits as the data bus width, specify mode data for the non-
multiplex external data bus 16-bit mode, and then the IOBS and LMBS areas are set up for 16-bit
size access. To set up the HMBS area for 16-bit size access, change the HMBS setting.
MD0 Mode name
External
0 0
vector mode 0
External
0 1
vector mode 1
External
1 0
vector mode 2
Internal vector
1 1
mode
0 0
0 1
1 0
FLASH writer
1 1
write mode
or 1=V
SS CC
Reset vector
access area
External
External
External
Internal
Setting is prohibited
FLASH serial writing
-
. For external vector mode 2, the data bus width also has a
CHAPTER 7 MODE SETTING
External
data bus Remarks
width
Reset vector
Multiplex
8-bit bus width
mode
access
Reset vector
Multiplex
16-bit bus width
mode
access
Non- Reset vector
multiplex 8-bit bus width
mode access
Operation after
reset sequence is
Mode data
controlled with
mode data
- -
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