User's Manual
Table Of Contents
- GC864 QUAD V2andGC864 DUAL V2Hardware User Guide
- APPLICABILITY TABLE
- 1 Introduction
- 2. Overview
- 3. GC864 Mechanical Dimensions
- 4. GC864-QUAD V2 / GC864-DUAL V2 Module Connections
- 5. Hardware Commands
- 6. Power Supply
- 7. Antenna
- 8. Logic Level Specifications
- 9. Serial Ports
- 10. Audio Section Overview
- 11. General Purpose I/O
- 11.1. GPIO Logic Levels
- 11.2. Using a GPIO Pad as INPUT
- 11.3. Using a GPIO Pad as OUTPUT
- 11.4. Using the RF Transmission Control GPIO4
- 11.5. Using the RFTXMON Output GPIO5
- 11.6. Using the Alarm Output GPIO6
- 11.7. Using the Buzzer Output GPIO7
- 11.8. Magnetic Buzzer Concepts
- 11.9. Using the Temperature Monitor Function
- 11.10. Indication of Network Service Availability
- 11.11. RTC Bypass Out
- 11.12. DAC Converter
- 11.13. ADC Converter
- 12. Assembly the GC864-QUAD V2 / GC864-DUAL V2 on the Board
- 13. Packing System
- 14. Conformity Assessment Issues
GC864 Hardware User Guide
1vv0300874 Rev.0 – 2010-01-25
Reproduction forbidden without Telit Communications S.p.A. written authorization - All Rights Reserved. Page 20 of 64
5.2.1. Hardware Unconditional Restart
WARNING:
The hardware unconditional Restart must not be used during normal operation of the
device since it does not detach the device from the network. It shall be kept as an
emergency exit procedure to be done in the rare case that the device gets stacked
waiting for some network or SIM responses.
To unconditionally Restart the GC864-QUAD V2 / GC864-DUAL V2, the pad RESET#
must be tied low for at least 200 ms and then released.
The maximum current that can be drained from the RESET# pad is 0,15 mA.
A simple circuit to do it is:
NOTE:
Do not use any pull up resistor on the RESET* line nor any totem pole digital output.
Using pull up resistor may cause latch up problems on the GC864-QUAD V2 / GC864-
DUAL V2 power regulator and improper functioning of the module. The line RESET*
must be connected only in open collector configuration.
TIP:
The unconditional hardware reboot must always be implemented on the boards and
the software must use it as an emergency exit procedure.