CHAPTER 3 HARDWARE SETTINGS AND FUNCTIONS
User’s Manual U17029EJ3V0UM
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3.6.3 Disconnecting QB-78K0MINI from related devices
Follow the steps described below when disconnecting the QB-78K0MINI from other related devices.
(1) Close the ID78K0-QB.
(2) Turn off the power to the target system (if using a target system).
(3) Remove the USB interface cable from the QB-78K0MINI and the host machine.
(4) Remove the QB-78K0MINI connection cable from the QB-78K0MINI and from either the target system or the
self-check board.
3.7 Pin Statuses at Power-on
Table 3-1 lists the statuses of pins at power-on.
However, when the USB interface cable is not connected, if the target voltage does not start up right away (V
DD
=
less than 2 V), the device may be degraded, so do not turn on the target’s power until after the USB interface cable
has been connected.
Table 3-1. Pin Statuses
Power-on Mode
Status of Target Interface Pin
USB Cable
Target Power Supply
Output Pin
Input Pin
Not connected
ON
All pins at low level
All pins at high impedance
Not connected
OFF
All pins at high impedance
All pins at high impedance
Connected
ON
Normal operation
Normal operation
Connected
OFF
All pins at high impedance
All pins at high impedance
