SIRETTA ZEST SERIES Quick user guide

inspired wireless technology
ZEST Series
GPRS/UMTS Wireless Modem with
RS232 Interface
Hardware Reference Manual
Rev 1.5

A member of the Olancha Group Ltd
Registered in England No. 08405712
VAT Registration No. GB163 04 0349
Siretta Ltd
Basingstoke Road
Spencers Wood
Reading
Berkshire RG7 1PW
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fax
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2
ZEST Series
GPRS/UMTS Wireless Modem with
RS232 Interface
Table of Contents
Page
Introduction 3
About Siretta 4
General Description 5
Specications 6
AT Commands 7
ZEST Interface 8
System Diagram 10
System Overview 11
Modes of Operation 12
Ordering Information 13
Dimensions 14
DIN Rail Mount 16
Mounting the ZEST 16
Removing the ZEST 16
ZEST Series Images 17
ZEST LED Indicator 18
Modem States 19
Interfaces 20
RS232 Serial Port Interface 20
RS485 Serial Port Interface (Optional) 22
ZEST-UMTS USB Serial Port Interface 23
USB Interface Drivers 24
SIM Socket 26
SIM Requirements 26
Antenna Connector 27
GSM/UMTS Antenna Connector 27
Power 29
ZEST-GPRS USB Power Connector 29
Power Connector
(2-pin 3.5mm Pluggable Terminal Block)
30
Power Supply Requirements 31
Current Consumption 33
Switching the Modem ON/OFF 34
Embedded Software Support 36
Telit AppZone 36
Telit Easy Script in Python 37
Siretta Recommends 38
Installation 40
Considerations for Installations
Incorporating the ZEST
40
Power Supply Installation 41
Securing the Modem 41
Safety and Product Care 42
General Precautions 42
SIM Card Precautions 42
Antenna Precautions 43
Exposure to RF Energy 43
Safety Recommendations 45
Conformity Assessment 46
Disclaimer 47
Denitions 48

A member of the Olancha Group Ltd
Registered in England No. 08405712
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3
ZEST Series
GPRS/UMTS Wireless Modem with
RS232 Interface
This document is intended to provide guidance when adding a modem from the
ZEST Series to your system.
The ZEST series of GPRS/UMTS M2M modems are a low cost range of modems
developed for easy integration into existing systems and for embedded application
development.
The ZEST modem range is based on the Telit xL865 GPRS/UMTS module series
without GPS. The modem manages the module power up sequence and can be
programmed to perform additional custom tasks.
This document discusses the modems hardware and software states and modes
of operation, in addition to the electrical characteristics of the modems interfaces.
Introduction

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4
ZEST Series
GPRS/UMTS Wireless Modem with
RS232 Interface
Siretta, located in Reading, United Kingdom have been manufacturing antennas,
cable assemblies and cellular modems for over 10 years. We supply our products
globally to many of the world’s leading organizations.
Whether you require an off the shelf or custom solution, Siretta has a wide portfolio of
antenna, RF cable assemblies and modems to t your application.
Our extensive knowledge and experience in the wireless market allows us to support
a wide range of customer applications, focusing on frequencies typically within the
75MHz - 5.8GHz range. These encompass the HF, VHF, ISM, GSM/GPRS/3G/4G
and GPS frequencies as well as industrial WLAN and VHF/UHF antenna/Wi-Fi
antenna solutions.
With a heavy emphasis on design, we have a team of dedicated Application
Engineers and Product Managers, backed up by Field Sales Engineers, who
specialise in wireless applications.
We have made signicant investments in R&D facilities which boast GPS hardware
development equipment and a GSM Pico Cell on site, as well as development
software and a comprehensive suite of Industrial, Scientic and Medical band, and
non ISM band frequency products. We have many technology partners enabling us to
keep at the forefront of the communications industry and offer class leading wireless
solutions.
About Siretta

A member of the Olancha Group Ltd
Registered in England No. 08405712
VAT Registration No. GB163 04 0349
Siretta Ltd
Basingstoke Road
Spencers Wood
Reading
Berkshire RG7 1PW
sales
fax
email
web
[phone]
[phone]
[email protected]
www.siretta.co.uk
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5
ZEST Series
GPRS/UMTS Wireless Modem with
RS232 Interface
The ZEST range of wireless modems is a compact cellular modem with RS232 port
(RS232 and USB on 3G model) and plastic housing, offering state-of-the-art 2G/3G
connectivity for machine to machine (M2M) applications.
Features
»Control via AT commands (Hayes 3GPP TS 27.007 and 27.005)
»TCP/IP, SMS and CSD access via AT commands
»1 x RS232 serial port
»1 x mini USB 2.0 high speed interface (available on 3G model only)
»Wide range input voltages
»Extreme operating temperature
»The plastic enclosure can be mounted on a DIN-rail or on the wall
General Description

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6
ZEST Series
GPRS/UMTS Wireless Modem with
RS232 Interface
Specications
ZEST-GPRS ZEST-UMTS
Standards: GSM/GPRS/EDGE GSM/GPRS/EDGE/UMTS/HSDPA/HSPA+
2G frequency band: 900, 1800MHz (EU Version) 900, 1800MHz (EU Version)
3G frequency band: -900, 2100MHz (EU Version)
Dimensions: 75 x 84 x 31mm 75 x 84 x 31mm
Weight: 105g 105g
Input voltage: 6 - 18V 6 - 26V
Power consumption: Idle: 50 - 60mA @ 12V Idle: 50 - 60mA @ 12V
Operating environment: -40 to +85°C
5 to 95% RH
-40 to +85°C
5 to 95% RH
GSM antenna connector: SMA Female SMA Female
USB interface: Mini USB (Power only) Mini USB 2.0 (Serial data and power)
Table 1. Specications of the ZEST modem

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7
ZEST Series
GPRS/UMTS Wireless Modem with
RS232 Interface
AT Commands
The ZEST range of wireless modems has a GSM engine at its heart which can be
controlled via the serial interface using standard AT commands.
The AT command is an ATTENTION command and is used as a prex to other
parameters in a formatted string. The AT command combined with other parameters
can be sent to the modem with your preferred modem emulator package (TMSTerm/
TeraTerm/HyperTerminal) and typed in manually as a command line instruction.
The wireless module is compliant with the following AT command formats:
1) Hayes standard AT command set, in order to maintain the compatibility with
existing SW programs.
2) 3GPP 27.007 specic AT command and GPRS specic commands.
3) 3GPP 27.005 specic AT commands for SMS (Short Message Service) and CBS
(Cell Broadcast Service)
4) FAX Class 1 compatible commands
5) Proprietary command set, the module family also supports a proprietary set of AT
commands for special purposes outside of the standard AT specication.
To obtain the latest AT command reference guide* with a full list of supported AT
commands, please contact your Siretta representative or alternatively visit:
www.siretta.co.uk
NOTE - This following document refers to useful AT commands throughout and offers
descriptions of how to use the AT commands with the ZEST wireless modems.
*For GPRS modems refer to the GPRS AT Command Manual, for UMTS modems refer to the
UMTS AT Command Manual.

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Registered in England No. 08405712
VAT Registration No. GB163 04 0349
Siretta Ltd
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Reading
Berkshire RG7 1PW
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8
ZEST Series
GPRS/UMTS Wireless Modem with
RS232 Interface
ZEST Interface
Standard Hardware Interfaces
The ZEST series modem comes with the following interfaces:
»1 x RS232 serial port interface for direct serial connection to module
»ZEST-GPRS: 1 x mini USB (Power only)
ZEST-UMTS: 1 x mini USB 2.0 (Serial data and power)
»1 x power connector (2-pin 3.5mm pluggable terminal block)
»1 x SMA female GSM antenna connector
»1 x SIM card reader (push-push)
»1 x external LED status indicator (Green)
Cellular Interface
The ZEST series modem comes with the following cellular interfaces:
»GPRS: Max 6.8kbps (DL & UL), Class 10
»EDGE: Max 236.8kbps (DL & UL), Class 12
»UMTS: Max 384kbps (DL & UL)
»HSDPA: Max 3.6Mbps / 384kbps (DL / UL)
»HSPA+: Max 7.2 / 5.76Mbps (DL / UL)
»CSD: Up to 9.6kbps
RS232 Serial Interface
The ZEST series modem comes with the following RS232 port interfaces:
»ESD protection: 15KV
»Parameters: 1200bps to 115200bps
»RS232: DCD, RxD, TxD, DTR, GND, DSR, RTS, CTS, RI
USB Port Interface
The ZEST series modem comes with the following USB port interfaces:
»ESD protection: 15KV
»5V power supply for modem

A member of the Olancha Group Ltd
Registered in England No. 08405712
VAT Registration No. GB163 04 0349
Siretta Ltd
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Spencers Wood
Reading
Berkshire RG7 1PW
sales
fax
email
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[phone]
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9
ZEST Series
GPRS/UMTS Wireless Modem with
RS232 Interface
Optional Gateway Software Package
The ZEST series modems have the following optional software packages available:
»V-Link232 Software
Wireless cable replacement using RS232 serial cable over GPRS/UMTS
Optional Coverage
The ZEST series modems have the following coverage options available:
»(EU) European Union
»(NA) North America
Optional Technologies
The ZEST series modems have the following optional technologies available:
»European GPRS (2G)
»European UMTS (3G)
Optional Modem Features*
Optional Hardware
The ZEST series modems have the following optional hardware features:
» RS485 serial port (serial interface: Data+ (A), Data- (B), GND)
*To add optional features on your modem, see ordering Information on page 13

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Registered in England No. 08405712
VAT Registration No. GB163 04 0349
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Berkshire RG7 1PW
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10
ZEST Series
GPRS/UMTS Wireless Modem with
RS232 Interface
System Diagram
Figure 1. ZEST system diagram
The ZEST is the latest in the Siretta range of cellular modems. It is the lowest cost of
the range and is ideal if all you need is straightforward GPRS connectivity - simply. It
competes strongly on its robust and industrial spec using Telit technology and with
RS232 and USB interfaces*.
GSM
PSU Power Input
SIM
RS232 Serial Port Interface
Visual Indicators
Power Supply Subsection
Communication Subsection
USB Port
Telit xL865 Module
* USB interface only provides power for ZEST-GPRS and provides serial data and power for
ZEST-UMTS.

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VAT Registration No. GB163 04 0349
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Berkshire RG7 1PW
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11
ZEST Series
GPRS/UMTS Wireless Modem with
RS232 Interface
This ZEST can be used in a number of applications, some examples are shown
below:
»V-Link232 Software (Wireless cable replacement using RS232 serial cable over
GPRS/3G)
»GPIO Monitor (Monitor/Set and report on GPIO status)
»Standard RS232 modem attached to existing equipment (PC/MAC/Server etc.)
Typically connected devices are:
»PC/MAC/Linux platforms for use as modem
»Embedded (connected directly to remote equipment without a PC attached)
Operating System Connected Modem
»Internet enable a remote device with RS232 connectivity over 2.5G/3G. Internet
connectivity can be retrotted to end equipment without changing the software or
conguration of the remote device.
»Used in countries or places where broadband and WiFi is a less common method
to connect to the internet or where services are unavailable. The ZEST modem
can overcome this restriction by providing a mobile internet solution over the
GPRS/3G network.
Embedded Systems
The V-Link software can be used with an embedded system where automated end to
end communication is required.
If the embedded system has limited intelligence or has limited conguration capability
the Siretta V-Link software can be used to connect the system to a central server
easily and simply.
The V-Link software can also be used to control and manage the remote modem so
that the connection from the embedded system to the central server/control head
ofce is seamless and reliable.
System Overview

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12
ZEST Series
GPRS/UMTS Wireless Modem with
RS232 Interface
Examples:
»Vending machine where the head ofce would poll for drinks remaining/money
taken etc. This would be an on-demand pull to obtain results in real time.
»Monitoring AMR/temperature/equipment in a home, i.e. Interrogate lights etc.*
»Monitoring GPIO, i.e. Open doors/windows*
»Remote entry system, i.e. Send a message to the modem to open a gate/door to
allow access.*
»Streaming live data from remote system to a central location
»Remote printing applications (remotely print over the GPRS network)
»Polling remote devices for information to prevent an engineer callout
USB Interface
This is a USB standard Communication Device Class (CDC) device. This is provided
with a driving for the OS, i.e. a standard OS supported driver.
V-Link Software
Embedded systems can use the RS232 serial port to connect to a remote device to
a central server. The serial conguration supports most congurations and can be
changed either via the USB interface, or via SMS commands.
Modes of Operation
*NOTE: Requires additional hardware not supplied with the ZEST. Please speak to your
Siretta representative for more information.

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13
ZEST Series
GPRS/UMTS Wireless Modem with
RS232 Interface
Ordering Information
ZEST X XXXX (XXXX)
Module Type
N = Without GPS
Product Module Version
GPRS (EU) = European Coverage of GPRS Technology
GPRS (NA) = North American Coverage of GPRS Techology
UMTS (EU) = European Coverage UMTS Technology
UMTS (NA) = North American Coverage of UMTS Technology
Software Package/Hardware Options
(V-Link232) = V-Link232 Software
(485) = RS485 Serial Port Interface
Part Numbering Examples
»ZEST-N-GPRS (EU) = EU Coverage GPRS Wireless Modem with RS232 Interface, without GPS
»ZEST-N-UMTS (EU) (V-Link232) (485) = EU Coverage UMTS Wireless Modem with RS485 and USB
Serial Port Interfaces and V-Link232 Software
Modem Identier
ZEST = Wireless Modem with RS232 and USB Serial
Port Interfaces
- -

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14
ZEST Series
GPRS/UMTS Wireless Modem with
RS232 Interface
Dimensions
All dimensions are shown in mm. The mounting holes are suitable for a M3 xing
screwing. These drawings are relevant for the entire ZEST series modems.
Figure 2. ZEST modem front view - dimensions
75.20
83.70
79.28
32.90
30.60

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15
ZEST Series
GPRS/UMTS Wireless Modem with
RS232 Interface
Figure 3. ZEST modem side view - dimensions
75.20
83.70
79.28
32.90
30.60

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ZEST Series
GPRS/UMTS Wireless Modem with
RS232 Interface
DIN Rail Mount
Figure 4. Mounting ZEST to DIN rail Figure 5. Removing ZEST from DIN rail
The ZEST has an integrated DIN rail mount housing which allows the unit to
connect on to the standard rail widely used for mounting industrial control
equipment inside equipment racks. This has been adopted as a European (EN)
and International (ISO) Standard.
Hook the bottom modem DIN rail clip onto the
bottom of the DIN rail
Push modem 45° until the top DIN rail clip locks
onto the top of DIN rail
1
2
1
2
Mounting the ZEST Removing the ZEST
Slide DIN rail clip upwards
Pull modem 45° until the top DIN rail clip unlocks
from the top of DIN rail
Slide modem down, until bottom DIN rail clip
unlocks from the bottom of the DIN rail
1
2
1
2
3
3
1:1 @ A3 Sheet Size
A B C D E F G H I
7
6
5
4
3
I H G F E D C B
2
A
1
AMENDMENTS
JOB NUMBER
Concept
DRAWING TITLE
STATUS
PROJECT INFO
UK
COPYRIGHT WARNING
These drawings and designs remain
the property of Sequoia Technology
Group. Any unauthorised use will
render the offender liable for damages.
ALL DIMENSIONS ARE IN Millimeters UNLESS OTHERWISE
STATED
SA11214
4.0
Complete assembly
Robustel Enclosure
Mounting
Siretta
06/02/2014
B.Hulman
DRAWING: X:\Sequoia Design\Siretta\Robustel Module\ Robustel Assembly
MODEL: X:\Sequoia Design\Siretta\Robustel Module\ Robustel Assembly
DESIGNER
26/08/2014
ISSUE DATE
DO NOT SCALE OFF DRAWING
EMAIL [email protected] FOR DXFS OR OTHER
SCALABLE FILES.
Page No: 08 /08
GENERAL NOTES:
PART NUMBER
REV
SCALE
4.0_Updated colour and added silk
screen_28/03/14_BH
3.0_Adjusted to suit findings from 3D
print prototypes. Added
logo._12/03/14_BH
2.0_Revised as per drawings supplied by
supplier_03/03/14_BH
1.0_Preliminary issue_07/02/14_BH
1:1 @ A3 Sheet Size
A B C D E F G H I
7
6
5
4
3
I H G F E D C B
2
A
1
AMENDMENTS
JOB NUMBER
Concept
DRAWING TITLE
STATUS
PROJECT INFO
UK
COPYRIGHT WARNING
These drawings and designs remain
the property of Sequoia Technology
Group. Any unauthorised use will
render the offender liable for damages.
ALL DIMENSIONS ARE IN Millimeters UNLESS OTHERWISE
STATED
SA11214
4.0
Complete assembly
Robustel Enclosure
Mounting
Siretta
06/02/2014
B.Hulman
DRAWING: X:\Sequoia Design\Siretta\Robustel Module\ Robustel Assembly
MODEL: X:\Sequoia Design\Siretta\Robustel Module\ Robustel Assembly
DESIGNER
26/08/2014
ISSUE DATE
DO NOT SCALE OFF DRAWING
EMAIL [email protected] FOR DXFS OR OTHER
SCALABLE FILES.
Page No: 08 /08
GENERAL NOTES:
PART NUMBER
REV
SCALE
4.0_Updated colour and added silk
screen_28/03/14_BH
3.0_Adjusted to suit findings from 3D
print prototypes. Added
logo._12/03/14_BH
2.0_Revised as per drawings supplied by
supplier_03/03/14_BH
1.0_Preliminary issue_07/02/14_BH

A member of the Olancha Group Ltd
Registered in England No. 08405712
VAT Registration No. GB163 04 0349
Siretta Ltd
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Spencers Wood
Reading
Berkshire RG7 1PW
sales
fax
email
web
[phone]
[phone]
[email protected]
www.siretta.co.uk
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17
ZEST Series
GPRS/UMTS Wireless Modem with
RS232 Interface
ZEST Series Images
Figure 8. ZEST - DIN rail mounted
Figure 7. ZEST power, USB & RS232 interfacesFigure 6. 3D view of the ZEST

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18
ZEST Series
GPRS/UMTS Wireless Modem with
RS232 Interface
ZEST LED Indicator
The ZEST has 1 LED output that easily indicates the functional/operational state of
the modem.
Table 2. LED status
Name Colour Status Description
POWER Green ON ZEST is powered on
POWER Green OFF ZEST is powered off
Figure 9. LED
Green LED

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19
ZEST Series
GPRS/UMTS Wireless Modem with
RS232 Interface
Table 3. Modem states (assume AT#SLED=2*)
Current Modem State Input Next state Indication of new state
Power Off Connect power Run Mode Green LED will be on
continuously
Run Mode Insert a valid SIM card On Network Green LED will be on
continuously
On Network Remove power Power off No activity on LED
Run Mode Remove power Power off No acitivity on LED
Power Off Connect power Run Mode Green LED will be on
continuously
Run Mode Insert a valid SIM card On Network Green LED will be on
continuously
NOTE - Normal Operation: When the modem is rst switched on with a valid SIM card, the
green LED will be on continuously. The modem will attempt to join a network and should take
about 10-15 seconds (this may vary considerably) whilst the modem searches for the network.
During this period you can determine the registration status of the network using the AT
command ‘AT+CREG?’ which will return one of 4 states as shown below:
+CREG: 0,1 – Indicates that the modem is registered to the home network
+CREG: 0,2 – Indicates that the modem is searching for a network
+CREG: 0,3 – Indicates that the modem has been denied network access
+CREG: 0,4 – Indicates that the modem has a network problem
+CREG: 0,5 – Indicates that the modem is registered to a roaming network
If the response ‘+CREG:0,2’ is returned for a long period of time (more than 5 minutes) then
this suggests that there may be a problem with the SIM setup, the network signal or the
antenna connection.
The current modem state and function is shown below in table 3.
Modem States

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20
ZEST Series
GPRS/UMTS Wireless Modem with
RS232 Interface
RS232 Serial Port Interface
This connector provides a serial RS232 communication between the ZEST modem
and the connected equipment. The modem can be congured via the RS232
connection using AT commands as specied in the AT command manual.
Pin Name Direction Status Direction
1DCD Output from UART that indicates the carrier is present Connected OUT
2RXD Output transmit line of UART Connected OUT
3TXD Input receive line of UART Connected IN
4DTR Input to UART and controls DTE ready condition Connected IN
5GND Ground Connected IN
6DSR Output from UART that indicates the module is ready Connected OUT
7 RTS Request to Send - Input line of UART that controls hardware ow control Connected IN
8 CTS Clear to Send - Output line of UART that controls hardware ow control Connected OUT
9 RI Ring Indicator - Output line of UART that indicates the incoming call condition Connected OUT
Table 4. Pin usage
Figure 10. RS232 serial port
RS232 port
Figure 11. Pin numbering
5
9
1
6
Interfaces