User's Manual
Table Of Contents
- 1 Overview
- 2 GE864-QUAD V2 Mechanical Dimensions
- 3 GE864-QUAD V2 module connections
- 4 Hardware Commands
- 5 Power Supply
- 6 Antenna
- 7 Logic level specifications
- 8 Serial Ports
- 9 Audio Section Overview
- 10 General Purpose I/O
- 10.1 GPIO Logic levels
- 10.2 Using a GPIO Pad as INPUT
- 10.3 Using a GPIO Pad as OUTPUT
- 10.4 Using the RF Transmission Control GPIO4
- 10.5 Using the RFTXMON Output GPIO5
- 10.6 Using the Alarm Output GPIO6
- 10.7 Using the Buzzer Output GPIO7
- 10.8 Indication of network service availability
- 10.9 RTC Bypass out
- 10.10 External SIM Holder Implementation
- 11 DAC and ADC section
- 12 Conformity Assessment Issues
- 14 Document Change Log
GE864-QUAD V2 Hardware User Guide
1vv0300841 Rev.0.1 24/11/09
Reproduction forbidden without Telit Communications S.p.A. written authorization - All Rights Reserved page 40 of 65
9 Audio Section Overview
The Base Band Chip of the GE864-QUAD V2 Telit Module provides two different audio blocks; both in
transmit (Uplink) and in receive (Downlink) direction:
“MT lines” should be used for handset function,
“HF lines” is suited for hands -free function (car kit).
These two blocks can be active only one at a time, selectable by AXE hardware line or by AT
command.The audio characteristics are equivalent in transmit blocks, but are different in the receive
ones and this should be kept in mind when designing.
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