CHAPTER 2 PIN FUNCTIONS
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User’s Manual U14359EJ4V0UM
(vii) RD (Read strobe) ··· 3-state output
This strobe signal shows that the bus cycle currently being executed is a read cycle for the SRAM,
external ROM, external peripheral I/O, or page ROM area. In the idle state (TI), it becomes inactive.
(viii) WE (Write enable) ··· 3-state output
This signal shows that the bus cycle currently being executed is a write cycle for the DRAM area. In
the idle state (TI), it becomes inactive.
(ix) OE (Output enable) ··· 3-state output
This signal shows that the bus cycle currently being executed is a read cycle for the DRAM area. In
the idle state (TI), it becomes inactive.
(x)
BCYST (Bus cycle start timing) ··· 3-state output
This outputs a status signal showing the start of the bus cycle. It becomes active for 1-clock cycle
from the start of each cycle. In the idle state (TI), it becomes inactive.
