Applicable Products Part number Description
ZETA-NLP-LTE1 (EU) Ultra Low Power European LTE Cat 1 Modem
ZETA-NLP-LTEM (GL) Ultra Low Power Global LTE Cat M Modem
Objective Power consumption is one of the key requirements of any Wireless IoT application.
A significant contributor to power consumption in such systems is the Cellular modem.
This application note shows how to set Siretta ZETA NLP modem in ultra-low power mode for reduced energy consumption.
Solution ZETA-NLP Ultra Low Power Mode The ZETA-NLP has a special mode of operation which forces the unit to drop down to an ultra-low power state where the modem is still operational and registered on the network but is functionally asleep. This allows for the modem to remain connected to the network and be ready to send and receive data using a fraction of the energy.
This ultra-low power state is achieved by setting the following AT command to the modem:
COM3 - Tera Term VT
File Edit Setup Control Window Help
AT CFUN=5
OK
Ultra Low Power Control Signal To control the power state of the modem from low power to ultra-low power it is necessary to use a special control signal in the RS232 serial port.
The control signal is called Data Terminal Ready (DTR) and is available on the RS232 serial port on pin 4 as shown in the table below.
Once the CFUN=5 command has been issued then the modem is ready to enter ultra-low power mode. To activate low power mode and put the modem in to a dormant state the DTR line must be de-asserted on the serial port. When the device has entered ultra-low power mode the CTS line will be de-asserted indicating that the device has gone into ultra-low power state. At this point the serial port is also deactivated, and the modem will not respond to AT commands and will appear to be OFF.
To bring the modem back to normal power state and communicate with the modem again it is necessary to assert the DTR line and the modem will leave its dormant state and become fully active again for normal operation. When in the dormant ultra-low power state an incoming call request or incoming SMS will force the modem to enter its full power mode and the modem is able to be used as normal.
Pin Name Usage Status Direction
1 DCD Output from UART that indicates the carrier is present Connected OUT
2 RXD Output transmit line of UART Connected OUT
3 TXD Input receive line of UART Connected IN
4 DTR Input to UART and controls DTE ready condition Connected IN
5 GND Ground Connected IN
6 DSR Output from UART that indicates the module is ready Connected OUT
7 RTS Request to Send - Input line of UART that controls hardware flow control Connected IN
8 CTS Clear to Send - Output line of UART that controls hardware flow control Connected OUT
9 RI Ring Indicator - Output line of UART that indicates the incoming call condition Connected OUT
This mode allows the modem to consume little current whilst it is not in use but be available for use locally by asserting the DTR line. The modem power ON and power lines will remain active throughout and can also be used to turn the modem completely OFF.
DTR Control Software To control the DTR line on the modem and communicate with the AT command interface on the RS232 serial port it is necessary to use Terminal software which controls the DTR line. Siretta has tested the ZETA modem family with several terminal emulator applications which support DTR and RTS control signalling. Two recommended applications are shown below:
Realterm (Download Link)
Telit AT Controller
Ultra Low Power Receiving Data In the ultra-low power state, a special provision must be catered for when data is received from a connected socket to be output over the serial port.
In this mode it is necessary to run the serial port in the following state:
Enable hardware flow control with AT&K3
Enable low power mode by issuing AT CFUN=5
Setup a socket connection and establish an active connection
Enter ultra-low power state by de-asserting DTR control line
De-assert RTS line
Wait for specified timeout to check for incoming data
When the timeout has expired, to check for data over the connected socket follow the procedure below:
Assert DTR line to disable low power state and activate full serial port
Assert RTS line to receive full buffered data over serial port and wait for all data to be received
When all data has been received de-assert RTS line
De-assert DTR line to re-enter low power state and wait for the specified timeout to receive further data.
NOTE - While there is no data pending reception from the cellular network, the modem does meet the published low power consumption figures. However, if there is data pending from the cellular network, then the modem power consumption rises to approximately 5mA at 12V until the data transfer process has completed and low power state is re-entered. The modem does not automatically enter the full power state when there is pending cellular network data, so the connected application is required to periodically poll the cellular network. If there is pending data from the cellular network, this will immediately start to be received over the serial connection.
Once the data transfer is complete, the modem can be put back into the low power state where it will meet the published power consumption figures. The shorter the check interval, the less time will be potentially spent at the higher 5mA current consumption. The longer the check interval the less power will be used checking for received data from the network. Choose this check interval to match the requirements of your system.
Demonstration of Solution Testing Ultra Low Power Mode using an Outgoing Socket Connection COM3 - Tera Term VT
File Edit Setup Control Window Help
//Set extended error
Europe Stories
11/12/2025
Dalet, a leading provider of cloud-native, end-to-end media workflow solutions, ...
03/12/2025
ToolsOnAir Composition Builder 2025 Boilerplate
More Details: The Composition Builder 2025 application for macOS enables TV stations and Live Event broadcast...
03/12/2025
ToolsOnAr just:live pro 2025 Boilerplate
More Details: just:live pro 2025 is a Single Channel Live Production Playout solution for video and static or real-t...
03/12/2025
ToolsOnAr just:play pro 2025 Boilerplate
More Details: just:play pro 2025 is a Single Channel automated 24/7 Master Control playout solution with SD, HD and ...
03/12/2025
ToolsOnAr live:cut 2025 Boilerplate
More Details: live:cut is an option to just:in mac pro 2025 and enables multicamera production workflows for up to 16 cam...
03/12/2025
ToolsOnAir Just In Mac Lite NDI 2025 Boilerplate
More Details: The Just In Mac Lite NDI application is a streamlined media capture solution designed specific...
03/12/2025
ToolsOnAir Just In Mac Lite 2025 Boilerplate
More Details: The Just In Mac Lite application is a streamlined media capture solution designed specifically for...
03/12/2025
ToolsOnAir just:in mac pro 2025 Boilerplate
More Details: just:in mac pro is a macOS-based client-server multichannel capture solution to record SDI, HDMI, N...
03/12/2025
Tracy Bonareri Onchoke, Thomson's Young Journalist of the year 2025 is hoping the accolade will be a springboard to more cross-border collaboration between ...
03/12/2025
For the fourth time, Bad Bunny is the most-streamed Wrapped artist on Spotify gl...
03/12/2025
The wait is over. It's time to look back at the audio that defined your year with 2025 Spotify Wrapped, our annual celebration for fans, artists, creators, ...
03/12/2025
Por cuarta vez, Bad Bunny es el Top Artista Global de Wrapped en Spotify, con 19...
03/12/2025
Spotify Wrapped is back, and as always, it's powered by the billions of streams that fans around the world delivered throughout the year. From the artists w...
03/12/2025
Spotify Wrapped is the moment when hundreds of millions of fans around the world...
03/12/2025
With more than 700 million listeners around the world turning to Spotify to soundtrack their lives, it's time to look back at the audio that defined the yea...
03/12/2025
Con m s de 700 millones de oyentes en todo el mundo usando Spotify para acompa ar su d a a d a, es momento de mirar hacia atr s y ver el audio que marc el a o....
03/12/2025
From page-turning thrillers to inspiring memoirs, audiobooks are becoming a core...
03/12/2025
Com mais de 700 milh es de ouvintes em todo o mundo recorrendo ao Spotify para embalar seu dia a dia, chega o momento de revisitar o udio que marcou o ano. Nos...
03/12/2025
Spotify Wrapped celebrates the audio that defined our year, and the annual globa...
03/12/2025
Wuppertal December 3, 2025
Riedel and Haivision Join Forces to Advance Wireless Video TransmissionRiedel Communications today announced a new partnership with...
03/12/2025
Tell us a little bit about your job I am a Digital Marketing Executive working on Paid Social, PPC, and Organic Social. I joined the team in May 2025 and am enj...
03/12/2025
SAN JOSE, Calif. and VIENNA - Dec. 3, 2025 - Harmonic (NASDAQ: HLIT) and Normann...
03/12/2025
S an Nollaig
Celebrate 2025's top Irish sporting stars with RT Sport Awards live from RT Studios on RT One and RT Player
RT pays tribute to Ror...
02/12/2025
eds3_5_jq(document).ready(function($) { $(#eds_sliderM519).chameleonSlider_2_1({...
02/12/2025
--
The International Electrotechnical Commission (IEC), the International Organization for Standardization (ISO), and the International Telecommunication Unio...
02/12/2025
Harmonic's cOS Platform Will Redefine Subscribers' Quality of Experience, Lowering Churn SAN JOSE, Calif. - Dec. 2, 2025 - Harmonic (NASDAQ: HLIT) today...
02/12/2025
S an Nollaig
Hollywood blockbusters The Banshees of Inisherin, Barbie and Oppenheimer make their Irish TV debut
Tune into the classics such as Love Actual...
02/12/2025
Showcasing fresh Irish storytelling and emerging talent Storyland 2025 signals a fantastic time for Irish drama
RT and F s ireann/Screen Ireland are proud to...
01/12/2025
MANCHESTER, UK - November 2025 - Announced two days before the 30th anniversary of Oasis' debut album, Definitely Maybe, the Oasis Live '25 tour marks t...
01/12/2025
01 Dec 2025
Kyivstar and Ukrainian Ministry of Digital Transformation Select Go...
01/12/2025
The prequel to the global hit Sky Original mob crime saga, Gomorrah' is a s...
01/12/2025
Featuring Florence Welch, Red Hot Chilli Peppers' Flea, designer Bella Freud...
01/12/2025
Fox Corporation Chief Financial Officer Steve Tomsic to Participate in Upcoming ...
01/12/2025
Arvato Systems' Virtual Private Cloud (VPC) Receives BSI C5 Certification (T...
01/12/2025
Summary This short video gives you an summary of the changes in under two minutes.
--...
01/12/2025
As the festive season approaches, RT Supporting the Arts is proud to showcase a...
01/12/2025
Festive specials of Christmas in Kilmainham presented by Marty Whelan, High Road Low Road, Callan Kicks the Year and Keys to My Life
Ring in the New Year with ...
01/12/2025
Architect and television presenter Hugh Wallace, best known to RT audiences as a long-serving judge on Home of the Year, has died at the age of 68.
In a state...
28/11/2025
It's easy to ignore those little red update available badges. But when it ...
28/11/2025
Friday 28 November 2025
Sky Sports x Slawn drop limited-edition football jersey...
28/11/2025
Rohde & Schwarz shows resilience in a challenging environment, revenue exceeds t...
28/11/2025
Unwrapped: The Toy Show Appeal - airing this Sunday on RT One and RT Player- s...
27/11/2025
27 Nov 2025
GSMA brings M360 Eurasia 2026 to Samarkand in partnership with VEON...
27/11/2025
Tahar Rahim and Izuka Hoyle star in the gripping six-part Sky Original from Acad...
27/11/2025
Thursday 27 November 2025
Sky Arts Reveals the Nation's Greatest Basslines - and Queen Reign Supreme
The UK's most iconic basslines have been revealed...
27/11/2025
Rating reflects rating progress across areas including policies, diversity & inclusion, health & safety and Net Zero leadership
Winchester, UK, 27 November 202...
27/11/2025
What are the industry standards for Retail Media? Kathryn explains that certification is based on the IAB Europe Retail Media Measurement Standards and the IAB ...
27/11/2025
World champion boxer and Irish sporting icon Katie Taylor will be in studio this...
27/11/2025
Roblox, one of the world's most popular online gaming platforms for primary ...
Applicable Products Part number Description 
