Telit Wireless Solutions UC864 manual Reset signal

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UC864-E Hardware User Guide

1vv0300766a Rev.1 - 31/01/08

7.1Reset signal

Signal Function

RESET Phone reset

I/O	PIN Number
I	54

RESET is used to reset the UC864-E module. Whenever this signal is pulled low, UC864-E is reset. When the device is reset it stops any operation. After the release of the reset UC864-E is unconditionally shut down, without doing any detach operation from the network where it is registered. This behavior is not a proper shut down because any device is requested to issue a detach request on turn off. For this reason the Reset signal must not be used to normally shutting down the device, but only as an emergency exit in the rare case the device remains stuck waiting for some network response.

The RESET is internally controlled on start-up to achieve always a proper power-on reset sequence, so there's no need to control this pin on start-up. It may only be used to reset a device already on that is not responding to any command.

NOTE: do not use this signal to turn off the UC864-E. Use the ON/OFF signal to perform this function or the AT#SHDN command.

Reset Signal Operating levels:

SignalMin Max

RESET Input high	2.0V*	2.2V

RESET Input low	0V	0.2V

* This signal is internally pulled up so the pin can be left floating if not used.

If unused, this signal may be left unconnected. If used, then it must always be connected with an open collector transistor, to permit to the internal circuitry the power on reset and under voltage lockout functions.

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Contents UC864 Hardware User Guide This document is relating to the following products UC864-E Hardware User GuideContents 10.4 10.311.1 11.2Disclaimer Overview Length 36.2 mm Width 30 mm Thickness 8mm Mechanical DimensionsPIN-OUT UC864-E module connectionsCmos Reserved Pin Signal Function 1 UC864-E Antenna connectorTurning on the UC864-E Hardware Commands10k Hardware shutdown Turning OFF the UC864-EHardware Unconditional Restart 10k +1.8 Power Supply Requirements Power SupplyUC864-E Hardware User Guide Electrical Design Guidelines General Design Rules1.2 + 12V input Source Power Supply Design Guidelines UC864-E Hardware User Guide Battery Source Power Supply Design Guidelines UC864-E Hardware User Guide Thermal Design Guidelines Power Supply PCB layout Guidelines Antenna Requirements AntennaAntenna Installation Guidelines Absolute Maximum Ratings -Not Functional Logic level specificationsOperating Range Interface levels Operating Range Interface levels 1.8V CmosReset signal Absolute Maximum Ratings Not Functional Serial PortsSignals of the UC864-E serial port are RS232 level translation UC864-E Hardware User Guide UC864-E Hardware User Guide 5V Uart level translation UC864-E Hardware User Guide Communication ports combinations USB PortGenerality Audio Section OverviewDefinitions SelectionInput lines microphone Electrical CharacteristicsEarMT Buffers Output lines speakerNot General Purpose I/OLogic level specifications Using the Alarm Output GPIO6 Using a Gpio Pad as InputUsing a Gpio Pad as Output Using the Buzzer Output GPIO7 LED status Device Status Indication of network service availabilityRTC Bypass out VAUX1 power outputOperating Range VAUX1 power supply Mounting UC864-E on your board USB Vbus Usbid Debug of the UC864-E in productionConformity Assessment Issues Safety Recommandations Revision Date Changes Document Change Log