Section 7 Wait-State Controller
7.1 Overview
To simplify interfacing to low-speed external devices, the H8/532 has an on-chip wait-state
controller (WSC) that can insert wait states (TW) to prolong bus cycles.
The wait-state function can be used in CPU and DTC access cycles to external addresses. It is not
used in access to on-chip supporting modules. The TW states are inserted between the T2 state
and T3 state in the bus cycle. The number of wait states can be selected by a value set in the wait-
state control register (WCR), or by holding the WAIT pin Low for the required interval.
7.1.1 Features
The main features of the wait-state controller are:
• Selection of three operating modes
Programmable wait mode, pin wait mode, or pin auto-wait mode
• 0, 1, 2, or 3 wait states can be inserted.
And in the pin wait mode, 4 or more states can be inserted by holding the WAIT pin Low.
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