User's Manual

UC864-E Hardware User Guide
1vv0300766a Rev.1 - 31/01/08
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4.2 Turning OFF the UC864-E
The turning off of the device can be done in three ways:
• By software command (see UC864-E Software User Guide)
• By hardware shutdown
• By Hardware Unconditional Restart
When the device is shut down by software command or by hardware shutdown, it issues to the
network a detach request that informs the network that the device will not be reachable any more.
4.2.1 Hardware shutdown
To turn OFF UC864-E, first, you MUST cut off supplying power to the USB_VBUS pin, then the pad
ON# must be tied low for at least 2 seconds and then released.
The same circuitry and timing for the power on shall be used.
The device shuts down after the release of the ON# pad.
NOTE: To turn OFF UC864-E, first of all, you MUST cut off supplying power to the USB_VBUS, or the module does
not turn off
TIP: To check if the device has powered off, the hardware line PWRMON should be monitored. When PWRMON goes
low, the device has powered off.