Panasonic PAN9520 Quick setup guide

Wireless Connectivity
PAN9520
EmbeddedWi-Fi Module
Module Integration Guide
Rev. 1.1

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PAN9520 Wi-Fi Module
Module Integration Guide Rev. 1.1 Page 2 of 44
Overview
The PAN9520 is a 2.4 GHz ISM band Wi-Fi
embedded module based on Espressif ESP32-S2,
which includes a wireless radio and a MCU for easy
integration of Wi-Fi connectivity into various
electronic devices.
Features
•Embedded 2.4 GHz Wi-Fi 802.11 b/g/n module
•Xtensa®single-core 32-bit LX7 microprocessor,
up to 240 MHz
•Chip internal 128 kB ROM, 320 kB SRAM, and
16 kB low power SRAM
•Integrated QSPI Flash and PSRAM (a variety of
memory densities are available)
•Ultra-Low Power (ULP) co-processor usable in
deep sleep mode
•All security features required for WPA2 and
WPA3 personal
•Espressif Integrated Development Framework
(ESP-IDF) with a multitude of examples available
for software development
•Supports 20 MHz and 40 MHz bandwidths in
2.4 GHz band with data rates up to 150 Mbps
•Simultaneous support for Infrastructure Station,
SoftAP, and promiscuous modes
•802.11mc Fine Time Measurement (FTM)
•36× programmable GPIOs with a rich set of
alternative functionalities:
−2× 12-bit SAR ADCs, up to 20 channels
−2× 8-bit DAC
−14× touch sensing IOs
−4× SPI (2× available for general purpose)
−1× I²S
−2× I²C
−2× UART
−RMT (Tx/Rx)
−LED PWM, up to 8 channels
−1× full-speed USB OTG
−1× DVP 8/16 camera interface (I²S resources
used)
−1× LCD interface (SPI2 resources used)
−1× LCD interface (I²S resources used)
Characteristics
•Surface Mount Type (SMT):
24 mm × 13 mm × 3.1 mm
•Tx power: up to 19.5 dBm at IEEE 802.11b
1 Mbps
•Rx sensitivity: -97 dBm at IEEE 802.11b 1 Mbps
•Power supply: 3 V to 3.6 V
•Current consumption 260 mA Tx (average at 11b,
11 Mbps), 76 mA Rx (40 MHz channel), 310 mA Tx
peak
•Deep sleep mode: <100 µA typical power
consumption (RTC timer only and VDD_SPI
disconnected)
•Wide temperature range from -40 °C to 85 °C
Block Diagram

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PAN9520 Wi-Fi Module
Module Integration Guide Rev. 1.1 Page 3 of 44
By purchase of any of the products described in this document the customer accepts the document's
validity and declares their agreement and understanding of its contents and recommendations. Panasonic
Industrial Devices Europe GmbH (Panasonic) reserves the right to make changes as required at any time
without notification. Please consult the most recently issued Module Integration Guide before initiating or
completing a design.
© Panasonic Industrial Devices Europe GmbH 2021.
This specification sheet is copyrighted. Reproduction of this document is permissible only if reproduction is
without alteration and is accompanied by all associated warranties, conditions, limitations, and notices. Do
not disclose it to a third party.
All rights reserved.
This Module Integration Guide does not lodge the claim to be complete and free of mistakes.
Engineering Samples (ES)
If Engineering Samples are delivered to the customer, these samples have the status “Engineering
Samples”. This means that the design of this product is not yet concluded. Engineering Samples may be
partially or fully functional, and they may differ from the published Product Specification.
Engineering Samples are not qualified and they are not to be used for reliability testing or series
production.
Disclaimer
The customer acknowledges that samples may deviate from the Module Integration Guide and may bear
defects due to their status of development and the lack of qualification mentioned above.
Panasonic rejects any liability or product warranty for Engineering Samples. In particular, Panasonic
disclaims liability for damages caused by:
•The use of the Engineering Sample other than for evaluation purposes, particularly the installation
or integration in another product to be sold by the customer,
•Deviation or lapse in function of the Engineering Sample,
•Improper use of the Engineering Sample.
Panasonic Industrial Devices Europe GmbH disclaims any liability for consequential and incidental
damages. In case of any queries regarding the Engineering Samples, please contact your local sales
partner or the related product manager.
The information contained herein is presented only as guidance for Product use. No responsibility is
assumed by Panasonic for any infringement of patents or any other intellectual property rights of third
parties that may result from the use of Product. No license to any intellectual property right is granted by
this document, whether express or implied, by estoppel or otherwise.
Description of hardware, software, and other information in this document is only intended to illustrate the
functionality of the referred Panasonic product. It should not be construed as guaranteeing specific
functionality of the product as described or suitable for a particular application.
Any provided (source) code shall not be used or incorporated into any products or systems whose
manufacture, use or sale is prohibited under any applicable laws or regulations.
Any outlined or referenced (source) code within this document is provided on an “as is” basis without any
right to technical support or updates and without warranty of any kind on a free of charge basis according
to § 516 German Civil Law (BGB) including without limitation, any warranties or conditions of title, non
infringement, merchantability, or fitness for a particular purpose. Customer acknowledges that (source)
code may bear defects and errors.

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PAN9520 Wi-Fi Module
Module Integration Guide Rev. 1.1 Page 4 of 44
The third-party tools mentioned in this document are offered by independent third-party providers who are
solely responsible for these products. Panasonic has no responsibility whatsoever for the performance,
product descriptions, specifications, referenced content, or any and all claims or representations of these
third-party providers. Panasonic makes no warranty whatsoever, neither express nor implied, with respect
to the goods, the referenced contents, or any and all claims or representations of the third-party providers.
To the maximum extent allowable by Law Panasonic assumes no liability whatsoever including without
limitation, indirect, consequential, special, or incidental damages or loss, including without limitation loss of
profits, loss of opportunities, business interruption, and loss of data.

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PAN9520 Wi-Fi Module
Module Integration Guide Rev. 1.1 Page 5 of 44
Table of Contents
1About This Document.........................................................................................................................6
1.1 Purpose and Audience ..............................................................................................................6
1.2 Revision History.........................................................................................................................6
1.3 Use of Symbols .........................................................................................................................6
1.4 Related Documents...................................................................................................................7
2Overview..............................................................................................................................................8
3PAN9520 Module.................................................................................................................................9
3.1 Block Diagram...........................................................................................................................9
3.2 Footprint ..................................................................................................................................10
3.3 Placement................................................................................................................................11
4Power Supply....................................................................................................................................13
5RF Path..............................................................................................................................................14
5.1 External Antenna.....................................................................................................................14
5.2 RF Trace..................................................................................................................................14
6Regulatory and Certification Information .......................................................................................16
6.1 Integration Measures for a Valid Approval...............................................................................16
6.2 General Certification Information.............................................................................................35
6.3 Federal Communications Commission (FCC) for US ..............................................................35
6.4 Innovation, Science, and Economic Development (ISED) for Canada ....................................38
6.5 European Conformity According to RED (2014/53/EU)...........................................................41
7Restricted Use...................................................................................................................................43
7.1 Life Support Policy...................................................................................................................43
7.2 Restricted End Use..................................................................................................................43
8Contact Details..................................................................................................................................44
8.1 Contact Us...............................................................................................................................44
8.2 Product Information .................................................................................................................44

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PAN9520 Wi-Fi Module 1 About This Document
Module Integration Guide Rev. 1.1 Page 6 of 44
1 About This Document
1.1 Purpose and Audience
This Module Integration Guide is intended to support the easy integration of the PAN9520 into a
product and to ensure the compliance with regulatory requirements.
This guide gives an overview about the hardware design requirements. It is intended for
hardware design, application, and Original Equipment Manufacturers (OEM) engineers.
Please read this guide carefully to assure the compliance of your product to regulatory.
The product is referred to as “the PAN9520” or “the module” within this document.
1.2 Revision History
Revision
Date
Modifications/Remarks
1.0
2021-05-31
First version
1.1
2021-06-07
Formal and structure changes.
Updated pictures: “Antenna Placement Recommendation”, “Footprint”.
Updated chapter “Placement”. Corrected footnote (no. 4): added macros.
Updated section “Modulation and Defining Power Limits for each available
Channel”: corrected byte “mpwr_cbw20_chan1” into
“mpwr_cbw20_chan14”.
Updated chapter “Regulatory and Certification Information”.
1.3 Use of Symbols
Symbol
Description
Note
Indicates important information for the proper use of the product.
Non-observance can lead to errors.
Attention
Indicates important notes that, if not observed, can put the product’s functionality
at risk.
Tip
Indicates useful information designed to facilitate working with the module and
software.
[chapter number]
[chapter title]
Cross Reference
Indicates cross references within the document.
Example:
Description of the symbols used in this document 1.3 Use of Symbols.
✓
Requirement
Indicates a requirement that must be met before the corresponding tasks can be
completed.

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PAN9520 Wi-Fi Module 1 About This Document
Module Integration Guide Rev. 1.1 Page 7 of 44
Symbol
Description
➔
Result
Indicates the result of a task or the result of a series of tasks.
This font
GUI Text
Indicates fixed terms and text of the graphical user interface.
Example:
Click Save.
Menu > Menu item
Path
Indicates a path, e.g. to access a dialog.
Example:
In the menu, select File > Setup page.
This font
File Names, Messages, User Input
Indicates file names or messages and information displayed on the screen or to
be selected or entered by the user.
Examples:
pan1760.c contains the actual module initialization.
The message Failed to save your data is displayed.
Enter the value Product 123.
Key
Key
Indicates a key on the keyboard, e.g. F10 .
1.4 Related Documents
For related documents please refer to the Panasonic website 8.2 Product Information.

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PAN9520 Wi-Fi Module 2 Overview
Module Integration Guide Rev. 1.1 Page 8 of 44
2 Overview
The PAN9520 is a 2.4 GHz 802.11 b/g/n embedded Wi‑Fi module based on Espressif's
ESP32-S2 that includes the powerful Xtensa 32-bit LX7 CPU. An integrated chip antenna and
QSPI memory enable the module to be used in a variety of stand-alone or host-controlled
applications. The integrated crystal ensures connection performance over full temperature
range and lifetime. The integrated crystal ensures connection performance over full temperature
range and lifetime. Although the PAN9520 is one of the smallest modules on the market, this
offers a rich set of peripherals like full-speed USB OTG, SPI, UART, I²C, and many more
1
.
The PAN9520 combines a high‑performance CPU, high‑sensitivity wireless radio,
baseband (BB) processor, Medium Access Controller (MAC), encryption unit, ROM bootloader,
chip-internal SRAM, and module-internal QSPI flash and PSRAM. Features as CCMP, TKIP,
WAPI, WEP, BIP, and an AES
2
accelerator enable the usage of secure data connections.
Parallel support of access point and station mode allows easy setup of simultaneous Wi‑Fi
connections from the module to smart devices and home network routers.
With the Espressif Integrated Development Framework (ESP-IDF), software can be developed
for a wide range of applications. At the same time, a huge number of software examples can be
used as starting point for the development.
Please note that the ESP-IDF is provided by Espressif Systems. Always use
the latest updates https://github.com/espressif/esp-idf.
For related documents please refer to 8.2 Product Information.
1
Compared to modules offering similar feature sets.
2
Counter Mode with CBC-MAC Protocol (CCMP); Temporary Key Integrity Protocol (TKIP); WLAN
Authentication and Privacy Infrastructure (WAPI); Wired Equivalent Privacy (WEP); Broadcast/Multitask
Integrity Protocol (BIP); Advanced Encryption Standard (AES)

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PAN9520 Wi-Fi Module 3 PAN9520 Module
Module Integration Guide Rev. 1.1 Page 9 of 44
3 PAN9520 Module
3.1 Block Diagram

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PAN9520 Wi-Fi Module 3 PAN9520 Module
Module Integration Guide Rev. 1.1 Page 10 of 44
3.2 Footprint
The outer dimensions have a tolerance of ±0.35 mm.
B1 B2 B3 B14B4 B5 B6 B7 B8 B9 B10 B11 B12 B13
A2 A3 A14A4 A5 A6 A7 A8 A9 A10 A11 A12 A13
C1 C14C11 C12 C13
D1 D14D11 D12 D13
E1 E14E11 E12 E13
F1 F14F11 F12 F13
G1 G14G11 G12 G13
H1 H2 H3 H14H4 H5 H6 H7 H8 H9 H10 H11 H12 H13
I1 I2 I3 I14I4 I5 I6 I7 I8 I9 I10 I11 I12 I13
A1
GT4
(Thermal GND)
GT1
(Thermal GND)
GT6
(Thermal GND)
GT3
(Thermal GND)
GT5
(Thermal GND)
GT2
(Thermal GND)
Top View
1.80 mm
1.00 mm
3.00 mm
9.00 mm
12.00 mm
24.00 mm
0.80 mm 1.40 mm 0.90 mm
1.40 mm 0.80 mm
4.00 mm5.00 mm4.00 mm
13.00 mm
3.30 mm
2.40 mm
2.40 mm
0.60 mm
0.60 mm
Antenna
Keep out Area

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PAN9520 Wi-Fi Module 3 PAN9520 Module
Module Integration Guide Rev. 1.1 Page 11 of 44
3.3 Placement
Antenna “Keep out Area”
Do not place any ground plane under the marked restricted antenna area in
any layer! This would be affecting the performance of the chip antenna in a
critical manner.
Impact of Placement on the Antenna Radiation Pattern
The placement of the module, surrounding material, and customer
components has an impact on the radiation pattern of the antenna.
The recommendation for the ground plane is based on a FR4 4-Layer PCB.
The following requirements must be met:
✓The supply voltage is free of AC ripple voltage (for example from a battery or a low noise
regulator output). For noisy supply voltages, provide a decoupling circuit (for example a
ferrite in series connection and a bypass capacitor to ground of at least 47 µF directly at the
module).
✓Do not stress the module mechanically when installed.
✓Keep this module away from heat. Heat is the major cause of decreasing the life time of
these modules.
✓Avoid assembly and use of the target equipment in conditions where the module
temperature may exceed the maximum tolerance.
✓Keep this module away from other high frequency circuits.
✓Refer to the recommended pattern when designing a board.
The antenna requires a cutout area of 5 mm × 3.3 mm under the PAN9520 module. This “Keep
out Area” shall be located in every layer under the module antenna. Note for example the “Keep
out Area” in all four layers of the PAN9520 evaluation board.
It is recommended to verify the perfect position of the module in the target application before
fixing the design.

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PAN9520 Wi-Fi Module 3 PAN9520 Module
Module Integration Guide Rev. 1.1 Page 12 of 44
Antenna Placement Recommendation
Use a ground plane in the area surrounding the module wherever possible.
All dimensions are in millimeters.
It is recommended to:
•Place the module in the center (horizontal) of mother PCB.
•Place the module at the edge (horizontal) of mother PCB with the antenna pointing
towards the outside.
•Extend the “Keep out Area” towards the mother PCB’s edge, if needed.
Antenna Placement Recommendation (Top View)
24.00
Min. 22.50
5.00
3.30
„Keep out
Area“
Min. 22.50 13.00
Min. 40.00
4.00
PAN9520
4.00

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PAN9520 Wi-Fi Module 4 Power Supply
Module Integration Guide Rev. 1.1 Page 13 of 44
4 Power Supply
The following conditions must be met:
✓The supply voltage is free of AC ripple voltage (for example from a battery or a low noise
regulator output). On the PAN9520 ETU, 10 µF decoupling capacitors on each supply
terminal are used for this purpose. If there is much noise on the power delivery network, a
filter network can be used intead.
✓Decoupling capactitors/networks are placed close to the module to reduce inductive effects.
✓The supply voltage is not exceedingly high or reversed. It should not carry noise and/or
spikes.
Power Terminals
There are three power terminals on the PAN9520. All are connected to the same 3.3 V power
net on the module.
Although the module could be powered via one terminal only, it is recommended to use all
terminals for distributing the currents. This will lead to a smaller voltage drop and thus a better
power integrity. Moreover, the supply’s return currents will also be distributed, which reduces
the galvanic coupling from the power net to signals and vice versa.
Power Terminals (red marked)
B1 B2 B3 B14B4 B5 B6 B7 B8 B9 B10 B11 B12 B13
A2 A3 A14A4 A5 A6 A7 A8 A9 A10 A11 A12 A13
C1 C14C11 C12 C13
D1 D14D11 D12 D13
E1 E14E11 E12 E13
F1 F14F11 F12 F13
G1 G14G11 G12 G13
H1 H2 H3 H14H4 H5 H6 H7 H8 H9 H10 H11 H12 H13
I1 I2 I3 I14I4 I5 I6 I7 I8 I9 I10 I11 I12 I13
A1
GT4
(Thermal GND)
GT1
(Thermal GND)
GT6
(Thermal GND)
GT3
(Thermal GND)
GT5
(Thermal GND)
GT2
(Thermal GND)
Top View
GPIO35GND GPIO36 GPIO37 GPIO38 GND U0TXD U0RXD GND GPIO45 GPIO46 CHIP PU VDD GND
GNDSPDT1SPDT2GPIO1NCNCVDD
VDD NCNCGNDNCGNDGPIO34
GPIO33
GND
MTCK
MTDO
MTDI
MTMS NC NC NC NC GPIO20 GPIO19 GND GND GND GPIO21 GND GND GND
GPIO14 GPIO13 GPIO12 GND
GPIO11 GND GPIO10 GND
GPIO7 GPIO8 GPIO9 GND
GPIO5 GND GPIO6 GND
GPIO2 GPIO3 GPIO4 GND
GNDRF padGNDGPIO0X32_PX32_NDAC 1DAC 2GNDVDD
VDD GNDNCGND
Antenna
Keep out Area

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PAN9520 Wi-Fi Module 5 RF Path
Module Integration Guide Rev. 1.1 Page 14 of 44
5 RF Path
5.1 External Antenna
Antenna Warning
The modular approval of the PAN9520 is only valid if the on-board antenna is
used. Other antennas have not been certified. OEMs must test the compliance
of the product by themselves, if other antennas are used in the end product.
The PAN9520 has a 50 RF pin (SMD pad). Connect an external antenna directly or via a
connector (e.g. U.FL) with RF trace to this RF pin. This RF trace shall be matched to 50 
5.2 RF Trace.
5.2 RF Trace
Ensure that the RF trace’s impedance is close to 50 . It is recommended to use a Coplanar
Waveguide with Ground (CPWG) as RF trace. The impedance is related to the trace width, the
distances of the trace to the ground layers and the material of the PCB.
The following design recommendation must be met:
✓The trace impedance is 50 .
✓The trace length is not exceeding 2 cm.
✓The Via fence is around the trace.
✓No other lines are crossed (power supply, interfaces, or clock traces)
Example RF Trace of the PAN9520 ETU
On the PAN9520 ETU (ENW49D01AZKF), the module’s RF pad is connected to an U.F.L.
connector. As an example, this RF trace is described in the following. The trace is shown in the
figure below (red marked). It can be observed that it is surrounded by a via fence as
recommended.
Substrate
SignalGND GND
GND

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PAN9520 Wi-Fi Module 5 RF Path
Module Integration Guide Rev. 1.1 Page 15 of 44
A critical point is the transition from the module to the mother PCB. Further simulations of the
transition and the RF paths help to determine e.g. the positions of ground vias around the RF
pad.
Dimensions of the used RF path:
•Trace width W = 178 µm
•Gap to GND G = 156 µm
•Copper thickness TH = 35 µm
•Height of substrate H = 127 µm
•Relative permittivity εr= 4.2
•Loss tangent tan δ = 0.021
H
G G
W
TH
εr, tan δ

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PAN9520 Wi-Fi Module 6 Regulatory and Certification Information
Module Integration Guide Rev. 1.1 Page 16 of 44
6 Regulatory and Certification Information
6.1 Integration Measures for a Valid Approval
The modular approval of the PAN9520 is only valid if the OEM satisfies several requirements.
These affect mainly the output power and the limitation of the operating channel range.
This section describes how both can be controlled and what are the measures for a valid
modular approval.
The PAN9520 is distributed without software and to OEMs only. The OEM is
responsible for using a software that complies with the local regulations.
PAN9520 evaluation tools must be distributed to OEMs only.
6.1.1 Limiting the Channel Range and Setting the Country Code
The range of channels, on which the PAN9520 can operate, has to be limited according to the
location of the module (or end product). The modular approval is only valid, if the OEM applies
the needed limitations in the developed software.
This section describes how the required limitations can be implemented.
Depending on the region the PAN9520 is operating in, the range of channels
must be limited accordingly. The OEM is responsible for implementing a
software that fulfills this requirement.
Channels must be limited to following ranges:
•FCC (USA): Channels 1 to 11
•IC (Canada): Channels 1 to 11
•RED (EU): Channels 1 to 13
The country code and channel limitations must not be changeable in the end
product/application.

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PAN9520 Wi-Fi Module 6 Regulatory and Certification Information
Module Integration Guide Rev. 1.1 Page 17 of 44
6.1.1.1 Country Code Setting with ESP-IDF
The Espressif Integrated Development Framwork (ESP-IDF) is the official software
development kit (SDK) for the ESP32-S2 IC used on the PAN9520. This contains the function
esp_wifi_set_country that can be used for setting the country code and limiting the channel
range. The function returns an error code of type esp_err_t. A pointer to a variable of type
wifi_country_t is needed as input. When the function is called, the settings of the linked input
variable (*country) are stored to the module’s flash memory.
The linked variable (type wifi_country_t) is a structure that contains all needed settings,
which are listed below.
For further details please refer to https://docs.espressif.com/projects/esp-
idf/en/v4.2/esp32s2/api-reference/network/esp_wifi.html?highlight=esp_wifi_set_coun-
try#_CPPv420esp_wifi_set_countryPK14wifi_country_t.
Structure of Type “wifi_country_t”
Name
Type
Example Settings
Description
cc3
char array
(3 bytes)
cc[0-2] = [‘D’, ‘E’, ‘ ’]
cc[0-2] = [‘U’, ‘S’, ‘ ‘]
cc[0-2] = [‘C’, ‘A’, ‘ ‘]
cc[0-2] = [‘E’, ‘U’, ‘ ‘]
This array of three characters contains
the two-digit country code
(ISO/IEC3166-1) and an environmental
setting (byte 3). Example codes are
given for Germany (DE), USA (US),
Canada (CA), and the European Union
(EU).
schan
uint8_t
1
Index of first channel of the allowed
range.
nchan
uint8_t
11
Number of channels in the allowed
range. The index of the last channel in
the range is schan + nchan - 1
max_tx_power
int8_t
56
Maximum Tx power in steps of 0.25 dBm
(valid values 8 to 78 ≙2 to 19.5 dBm)
policy4
wifi_country
_policy_t
WIFI_COUNTRY
_POLICY_MANUAL
Setting, if the configured country code is
always used, or if the module adapts to
the AP configuration (if it is station).
Details are given in the following.
3
Entries “0” and “1” contain the alpha-2 country code specified by ISO3166. For a list of codes please refer to
https://www.iso.org/obp/ui/#search/code/. Please note that there are also reserved codes that do not
represent a country but are valid as well. An example is “EU” for the European union.
4
The setting “policy” is of another custom datatype wifi_country_policy_t. Variables of this type are
enumerations with two valid numbers. The numbers are represented by following macros:
WIFI_COUNTRY_POLICY_AUTO and WIFI_COUNTRY_POLICY_AUTO.

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PAN9520 Wi-Fi Module 6 Regulatory and Certification Information
Module Integration Guide Rev. 1.1 Page 18 of 44
WIFI_COUNTRY_POLICY_AUTO
If the PAN9520 is configured as station, the used country code setting is adapted to the one of
the access point (AP), to which the station is connected.
Please note that not only the country code itself is changed, but also the
channel range.
After the station has been disconnected from the AP, the country code setting is reset to the
configured one.
If the module is in station mode, not connected to an AP and performs a scan, this scans
actively on channels schan to min{(schan + nchan -1), 11} of the configured country
code setting. The remaining channels schan + nchan to 14 (or 12 to 14 if
schan + nchan >= 12) are scanned passively. This ensures that regulations are not violated,
even if the configured country code does not match the location of the device.
Please note that hidden SSIDs on channels 12 to 14 can never be found, if
WIFI_COUNTRY_POLICY_AUTO is used.
If the module is in station mode, connected to an AP and performs a scan, the module uses the
country code settings of the AP. Hence, an active scan is performed on schan to
(schan + nchan -1) of the AP’s country code settings and a passive scan is performed on
the remaining channels.
If the module is set to station/AP coexistence mode, the configured country code settings are
used if the device has not been connected to another AP. If the device is connected to another
AP, the country code settings of the AP are used (also for the module’s AP).
If the module is configured as AP, this setting has no effect and the configured country code
settings are always used.
For further details please refer to https://docs.espressif.com/projects/esp-idf/en/v4.2/esp32/api-
guides/wifi.html#wi-fi-country-code.
WIFI_COUNTRY_POLICY_MANUAL
If the setting WIFI_COUNTRY_POLICY_MANUAL is used, the configured country code settings
are used in any case. Only channels in the valid range can be scanned actively.
For further details please refer to https://docs.espressif.com/projects/esp-idf/en/v4.2/esp32/api-
guides/wifi.html#wi-fi-country-code.

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PAN9520 Wi-Fi Module 6 Regulatory and Certification Information
Module Integration Guide Rev. 1.1 Page 19 of 44
Example 1 (US, Manual Policy)
If the module shall be e.g. only operated in the USA, the country code could be set accordingly
and the policy setting can be set to WIFI_COUNTRY_POLICY_MANUAL for ensuring that the device
cannot operate on prohibited channels in any case. A related application could be a product that
operates as AP and is sold in the US. Related example C code is given below.
#include "exmpl_error_check.h"
#include "esp_wifi.h"
esp_err_t error_code;
wifi_country_t cc_us_manual = {{'U', 'S', ' '}, 1, 11, 78, WIFI_COUNTRY_POLICY_MANUAL};
wifi_country_t* cc_us_manual_pt = &cc_us_manual;
error_code = wifi_set_country(cc_us_manual_pt);
check_error_code(error_code);
Example 2 (EU, Automatic Policy)
In this example, the country code is set to EU and channels “1”to “13”are enabled. The
maximum output power is limited to 16 dBm (6.1.2 Limiting the Output Power) and the policy
is set to WIFI_COUNTRY_POLICY_AUTO. This could be applicable for a product that acts as station
and is sold in the EU. If the device is operated in a non-EU region, the country code will be
adapted to the one of local APs. If the device is not connected to any AP, active scans will be
only performed on channels “1”to “11”. Channels “12”to “14”are scanned passively.
#include "exmpl_error_check.h"
#include "esp_wifi.h"
esp_err_t error_code;
wifi_country_t cc_eu_auto = {{'E', 'U', ' '}, 1, 13, 64, WIFI_COUNTRY_POLICY_AUTO};
wifi_country_t* cc_eu_auto_pt = &cc_eu_auto;
error_code = wifi_set_country(cc_eu_auto_pt);
check_error_code(error_code);
Further Readings
“Wi-Fi Country Code” general description: https://docs.espressif.com/pro-
jects/esp-idf/en/v4.2/esp32/api-guides/wifi.html#wi-fi-country-code
Function “esp_wifi_set_country”: https://docs.espressif.com/projects/esp-
idf/en/v4.2/esp32/api-reference/net-
work/esp_wifi.html#_CPPv420esp_wifi_set_countryPK14wifi_country_t
Data type “wifi_country_t”:https://docs.espressif.com/projects/esp-
idf/en/v4.2/esp32/api-reference/network/esp_wifi.html#_CPPv414wifi_coun-
try_t


PAN9520 Wi-Fi Module 6 Regulatory and Certification Information
Module Integration Guide Rev. 1.1 Page 20 of 44
6.1.1.2 Country Code Setting with ESP32-S2 AT Firmware
Instead of developing an embedded software for the PAN9520, an AT firmware provided by
Espressif can be used. This is based on the ESP-IDF and is available as source code or
precompiled binary.
This section explains how the country code settings can be applied if the AT firmware is used.
There are two commands related to the country code setting. These are AT+CWCOUNTRY?, which
will query the current country code information, and AT+CWCOUNTRY, which will set the country
code configuration and store it into flash. The input parameters are similar to those, used in
ESP-IDF (6.1.1.1 Country Code Setting with ESP-IDF) and are only explained briefly in the
following.
For further details, please refer to https://docs.espressif.com/projects/esp-at/en/release-
v2.1.0.0_esp32s2/AT_Command_Set/Wi-Fi_AT_Commands.html#at-cwcountry-configures-the-
wi-fi-country-code.
country_policy
0: Identical to WIFI_COUNTRY_POLICY_AUTO option in ESP-IDF
1: Identical to WIFI_COUNTRY_POLICY_MANUAL option in ESP-IDF
country_code
String of variable length (maximum 3) containing the country code. Please note that quotation
marks must be used to identify the parameter as string. Similar to cc[0-2] in ESP-IDF.
start_channel
Index of first channel allowed to use. Identical to schan in ESP-IDF.
total_channel_count
Number of channels that can be used. The index of the last channel is
start_channel + total_channel_count –1. Identical to nchan in ESP-IDF.
Example (Canada, Manual Policy)
This example illustrates the configuration via AT commands. The country code has been
chosen to be CA for Canada and the range of allowed channels are set to “1”to “11”
accordingly. The device shall always use the configured country code settings, which causes
the parameter country_policy to be one.