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How to use CLKOUT synchronization and CLKOUT asynchronization?

Latest Updated:02/01/2008

Question:

There are two sets of external bus specifications, CLKOUT synchronization and CLKOUT asynchronization, but how are they respectively used?

Answer:

If only a semiconductor device such as SRAM that can be satisfactorily controlled with address and data and simple control signals such as RD or WR is connected to the external bus, use the CLKOUT asynchronization specifications. If the CLKOUT asynchronization specifications are used, the design of timing with SRAM can be done comparatively simply.
If the device to be connected to the external bus cannot be controlled just by the control signals output from the CPU and more complex control signals are required (when control involving fine timing is required), the control signals may be generated through timing synchronized with the CLKOUT signal. In this case, use the CLKOUT synchronization specifications.
Suitable Products
V850 Family