Chapter 6 Cautions
memory board is installed.
•The data bus used for
•Although some of the address bus signals, data bus signals, and control lines of the memory board are connected to the user system, the chip select signal is not connected and thus the user system cannot access data in the memory board.
■Cautions to be observed when the
•When performing
•The following three conditions must be satisfied when the power supply is turned off by pow-
1.It takes 25 ∝s or more for all the power supply levels of the evaluation MCU to de- crease from 0.9 Vcc to 0.5 Vcc.
2.The CPU operating frequency is 1 MHz or higher.
3.A user program is being executed.
•For details on the
■Cautions to be observed when the external memory emulation function and the
•If the user power supply remaining high level is shut off with the External address and RDX pins, the bus hold feature of the buffer ICs on the adapter board causes a current of up to 250 mA to flow until each signal level goes low.
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