Wi-Fi FAQ’s

Serial to Wi-Fi

AT Commands

How do I connect the eS-WiFi module to a wireless network?

1. Set Access Point SSID
2. Set Access Point Password
3. Set Access Point Security Mode
4. Use DHCP?
5. Join Network
C1=eS-WiFI_Demo Set SSID
C2=LetMeInNow Set Password
C3=4 WPA2-Mixed
C4=1 Use DHCP
C0 Join


How do you save eS-WiFi parameters?

1. Set parameter
2. Z1 Save current settings
Ex. Set UART buad
U2=19200 Set buad rate to 19200
Z1 Save current settings
Next time the module is reset or power up the
baud rate will be 19200.

How do you send data using the eS-WiFi module?

1. Join Network (see How to join a network)
2. Setup a TCP/UDP connection (see How to setup a TCP/UDP Comm Server/Client)
3. Set number of bytes of data to be sent
4. Send data
S1=10 Set NOB to 10
S0\r0123456789 1 Send data
Note 1: \r = Carriadge Return, \n=New Line

How do set up a TCP Client?

1. Set Protocol to TCP
2. Set Remote Host IP Address
3. Set Remote Port
4. Start TCP Client
P1=0 Select TCP Protocol
P3= Set Host IP Address
P4=8001 Set Port 8001
P6=1 Start TCP Client

How do you setup a TCP Comm Server?

1. Set Protocol to TCP
2. Set Local port number
3. Start TCP Comm Sever
P1=0 Select TCP Protocol
P2=80 Set Port 80
P5=1 Start TCP Comm Server

How do set-up a UDP Comm Server using the eS-WiFi module?

1. Set Protocol to UDP
2. Set Local port number
3. Start UDP Comm Sever
P1=1 Select UDP Protocol
P2=5024 Set Port 5024
P5=1 Start UDP Comm Server

How do you setup a UDP Client on eS-WiFi?

1. Set Protocol to UDP
2. Set Remote Host IP Address
3. Set Remote Port
4. Start UDP Client
P1=1 Select UDP Protocol
P3= Set Host IP Address
P4=8001 Set Port 8001
P6=1 Start UDP Client

Do you include any drivers with your eS-Wifi modules?

The es-Wifi module is based on a simple AT command set that is used to communicate with the module. You can use a low cost 8/16/32 bit microcontroller to control the eS-WiFi module.

How to reset factory space on the eS-WiFi module?

1. Z3=0 Select factory space
2. Z2 Clear settings
3. ZR or Reset

How do I perform a factory reset on the Wi-Fi modules?

There are two ways to rest the module.

1.) To do a Soft reset type the AT command  <ZR>.


2.) Pull the module Reset pin low

How do I enable the UDP protocol on the eS-WiFi modules?

1. Set Protocol to UDP
2. Set Local port number
3. Start UDP Comm Sever
P1=1 Select UDP Protocol
P2=5024 Set Port 5024
P5=1 Start UDP Comm Server


How do I upgrade a eS-WiFi modules firmware?

Today, we recommend that you use a JTAG connector. We are currently working on two additional methods, use of the boot loader running inside the eS-WiFi or over the air. Over the air updates will require the use of an external SPI flash device to store the new image.



How am I informed of firmware updates to the eS-WiFi module?

All customers that register the eS-WIFI evaluation kits are automatically put on distribution for all firmware releases relative to the product purchased. If you would like additional people added to the update, please register the user in the “contact us” section of our web site.

Do you need a SLA to purchase the eS-WiFi modules?

Yes, we have a royalty free object code SLA agreement.

Host Interface

Which host microcontroller is recommended?

Any controller that has a UART or SPI interface can be connected  to the eS-WiFi module.

What interfaces do the eS-WiFi modules support?

You can use AT Commands over the UART, SPI or USB HID interface to send commands and send/receive data.

How do I connect the eS-Wifi module to my host microprocessor via UART?


Connect TX on the Module to RX on your Microcontroller
Connect RX on the Module to TX on your Microcontroller


Does eS-WiFi UART have RS-232 Transceiver?

No ,the module uses 3.3 volt logic.

How do I connect the eS-WiFi UART to my host microcontroller?

The module only require 6 wires to use the UART: TX, RX, Power, Ground and we recommend you also connect Reset and wakeup to your host.


Do the eS-WiFi L44 modules support SPI mode? What pins should I use to connect SPI?

Yes, the eS-WiFi modules support SPI.
The correct pins to use for the host I/O are the ADC1-ADC4 pins.

SPI Interface

SPI Interface on eS-WiFi L44 modules


Is the eS-WiFi module’s SPI interface slave or master?

The eS-WiFi SPI interface is a slave.

802.11 Standards

Do the eS-WiFi modules support 802.11 n?

Yes, we support 802.11 b/g/n.

Do you support both IPV4 and IPV6 network stack?

We support IPV4 today and will support IPV6 in the future.  Contact Inventek for further details.


Do you support SSL/TLS security?

We are developing SSL/TLS security capability for enabling HTTPS secure Webserver.

Do eS-WiFi modules support Wi-Fi Protected Setup (WPS)?

Yes, we support both methods of WPS (push button and PIN method).

What security protocols are supported by eS-Wifi modules?

We currently support : WEP, WPA, WPA2-PSK.

Do you support Enterprise Security in your modules?

Enterprise security is currently not supported but will be added early in 2013.  Please contact Inventek for further details.


Is Antenna diversity supported on eS-WiFi modules?

No, antenna diversity is not supported currently.

Can an external antenna be interfaced to eS-Wifi modules?

Yes.  We supply certain modules with U.FL connectors.  We use a “-U” at the end of the part number to designate those with the U.FL connector.  The ISM4319-M3-L44-U and ISM43362-M3G-L44-U have U.FL connectors and our antenna, part number w24-SSMA-M  has been FCC and CE certificertification.

We also recommend that you buy an SMA to U.FL adapter to connect your external antenna

Access Point

Do you have Ad-Hoc functionality?

The eS-WiFi SoftAP supports infrastructure mode for peer-to-peer connections.

Maximum number of supported sockets?

A maximum of eight (5) TCP or UDP sockets are supported on the ISM43362 module and two (2) for the ISM4319 module.

Does the SoftAP mode work with Android and iPhone as clients?

Yes…Es-WiFi modules operate in Infrastructure mode so both iOS and Android devices can connect.

Wi-Fi Direct

Do you support Wi-Fi Direct?

Modules are not officially certified as WiFi Direct, however our modules accomplish  Wi-Fi Direct using a “Direct Connect” mode. In the Direct Connect mode, the SoftAP is running on the module and you establish a direct infrastructure mode connection with the joining STA.

Demo Software

What are the basic instuctions for installing the eS-WiFi Demo program?

1. Download and install Drivers: http://inventeksys.com/wp-content/uploads/2012/02/Inventek_Systems_eS-WiFiDemo_v1.1_b12.zip
2. Save the es-Wifi Demo.Zip
3. Unzip and enter password (Located inside packaging box)
4. Run as Administrator

Can the eS-WiFi demo software run on any computer?

It can run on all Windows XP, Vista and Windows 7 operating systems.  We recommend that you right click on the application and run as Administrator. Some of the demo applications are designed to send and receive files and the application places files into the Inventek Systems <File> folder.


Do you supply drivers with the eS-WiFi firmware?

Drivers are NOT required to use eS-WiFi modules.  AT commands are sent over the serial interface (UART, SPI or USB).

FCC/CE Certification

What additional certifications do I need to have for my end product that uses your certified module?

Even though the eS-WiFi module is certified,  the end product will still have to go through a small portion of RF certification.  Also developers may need to apply for country specific certifications.

What certifications do your eS-WiFi modules have?

All eS-Wifi modules have FCC, IC and CE certification.


What is the range of your es-Wifi modules

The range varies depending on what antenna scheme you choice. The options are PCB etch and external. The distance depends on environmental conditions, but the range is approximately 250 meters line of sight with up to 5 Mbps Wi-Fi connection and 30 meters indoors through several walls.

Output Power

What is the transmit power of your eS-Wifi modules?

The transmit power is set to a max. output power level of 18 dBm .  This level is compliant with the FCC and CE regulatory standards.

On-Board Microcomputer

What microcomputer is used on the eS-WiFi module?

STMicroelectronics Cortex M3, ST32F103 and ST32F205.   The TCP/IP stack and WiFi firmware use one of these microcomputers.

Can we integrate our custom applications on the modules internal processor?

The internal processor of the modules is not accessible to the developer.  However, Inventek  offers the option of integrating your code with the on-board microcomputer’s firmware.  Please contact Inventek Systems for further details.


Are the es-WiFi modules footprint compatible?

Yes, all the currently available eS-WiFi modules are footprint compatible. (44 pin LGA)


Which drivers do you support for the ISM4319 SIP?

Linux, Android and WinCE drivers are available.