Fujitsu MB91F109 FR30 Hardware Manual page 189

specified areas are 8 bits wide, D23 to D16 automatically become I/O ports, which are set to
High-Z.
The above example shows the case, where D23 to D16 and WR1X are used as I/O ports. If
the bus width of at least one of chip select areas 0 to 5 is set to 16 bits, D23 to D16 and
WR1X cannot be used as I/O ports.
Pin
Maximum bus width
16 bits
8 bits
• DACK0 to DACK2 and E0P0 to E0P2 are output in external bus cycles. The DMAC register
specifies whether to output these signals. The output time is the same as WR0X to WR1X.
D31-24
WR0X
D31-24
WR0X
D31-24
WR0X
4.17 Bus Timing
D23-16
WRIX
D23-16
WRIX
I/O port
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