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(b) Control mode (external expansion mode)
P40 to P47 can be set as AD0 to AD7 according to the contents of the memory expansion register (MM).
(i)
AD0 to AD7 (Address/Data 0 to 7) ··· 3-state I/O
These are multiplexed address/data bus that is used for external access. Under address timing (T1
state), these pins operate as AD0 to AD7 (22-bit address) output pins. Under data timing (T2, TW, T3),
they operate as low-order 8-bit I/O bus pins for 16-bit data. The output changes in synchronization with
the rising edge of the clock in each state within the bus cycle. When the timing sets the bus cycle as
inactive, these pins are set for high impedance.
(6) P50 to P57 (Port 5) ··· 3-state I/O
Port 5 is an 8-bit I/O port in which input and output pins can be specified bitwise.
P50 to P57 can function as I/O port pins and can also operate as a time division address/data bus (AD8 to AD15)
when using external memory expansion. These pins can be set bitwise to port mode or a control mode.
The I/O signal level uses the bus interface power supply pins BV
(a) Port mode
P50 to P57 can be set bitwise as input or output pins according to the contents of port 5 mode register
(PM5).
(b) Control mode (external expansion mode)
P50 to P57 can be set as AD8 to AD15 according to the contents of the memory expansion register (MM).
(i)
AD8 to AD15 (Address/Data 8 to 15) ··· 3-state I/O
These are multiplexed address/data bus that is used for external access. Under address timing (T1
state), these pins operate as AD8 to AD15 (22-bit address) output pins. Under data timing (T2, TW,
T3), they operate as high-order 8-bit I/O bus pins for 16-bit data.
synchronization with the rising edge of the clock in each state within the bus cycle. When the timing
sets the bus cycle as inactive, these pins are set for high impedance.
(7) P60 to P65 (Port 6) ··· 3-state I/O
Port 6 is a 6-bit I/O port in which input and output pins can be specified bitwise.
P60 to P65 can function as I/O port pins and can also operate as an address bus (A16 to A21) when using
external memory expansion. These pins can be set bitwise to port mode or a control mode.
The I/O signal level uses the bus interface power supply pins BV
42
CHAPTER 2
PIN FUNCTIONS
DD
DD
and BV
as a reference.
SS
The output changes in
and BV
as a reference.
SS
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