WIFI module supporting Contention-Free-Service.

Hi Simon,

Any CC32xxMOD or CC31xxMOD module meets that points. But if you want to use module without application processor (capability to run own code inside module), you can use CC31xxMOD devices. All CC32xx/CC31xx devices supports transceiver mode which allow to use IEEE 802.11 PHY as your own connection- less transceiver.

Jan

Hi Jan,

Thank you for answer.

Can CC31xxMOD module be used in AP Mode?

In the data sheet, it is labeled Soft AP.

Can I use Contention Free Service in Soft AP mode?

Regards,
Simon

Hi Simon,

Yes CC31xxMOD devices supports AP mode. CC3100 supports AP mode for one connected client, CC3120/CC3135 supports up to four clients.

No. AP mode (Soft AP) is a connected mode. By natural behaviour/design of any WiFi device is that AP mode cannot be a connection-less service.

Jan

Hi Jan,

This sounds promising, and one more question.

We want to make our own MAC layer protocol, for response time critial Factory Automation application, which has one hunder slave devices with need tiny bits of TX/RX data each.

Basically, we do not want to be limted by 802.11 mac protocol, which has lots of backoff time and number of connection limits.

If we use CC31xxMOD in transceiver mode, can we fully bypass 802.11 MAC protocl, which has backoff time and connection limit?

Regards,
Simon

Hi Simon,

Yes, it is achievable at transceiver mode with CC31xx devices. As I remember one of e2e forum user had developed own mesh network solution with CC3200 devices.

Btw ... Why you want to develop own MAC layer with WiFi PHY? This can be pretty challenging thing. It should be much easier to use wireless SoC (Sub-1GHz or 2.4GHz) with capability for protocols like a Thread, Zigbee, or 6LoWPAN.

Jan

Hi Jan,

Your advice was very helpful.

I want to try the project.

Please help me in configuring the development environment.

================================================================
1. EVB
Which product should I purchase from the following URL?
www.ti.com/.../CC3120MOD

2. SDK
Where can I download the SDK that supports Non-OS?
================================================================

Regards,
Simon

Hi Simon,

This depends on your host processor. To be able use CC3120MOD with non SimpleLink devices (MSP432, some CCxxxx chips) you need to port host driver to your platform. This can be challenging thing and it will require some resources at your main MCU. As resource of information you should use SIMPLELINK-SDK-WIFI-PLUGIN, SWRU455 at chapter 19. Information sources are mainly related to RTOS implementation, but at e2e forum you find some threads related porting host driver to non-RTOS environment.

I think for start you should buy:

• BOOSTXL-CC3120MOD (CC3120MOD itself at board)
• CC31XXEMUBOOST (allow to easy programming content of internal sFlash using Uniflash software)
• MSP-EXP432P401R (LaunchPad which allow to start development with examples prepared by TI already; although MSP432 is not your main MCU, usage of MSP432 which have already ported driver, can help you at beginning)

But there can be another way. You can use CC3220MOD and prepare your own MAC firmware for them. Communication with your main MCU will be via your own protocol (e.g. UART, SPI) and your MAC stack will run inside Application processor (Cortex-M4). This approach will off-load your main MCU from any MAC stack handling. BOM price will be similar and you porting of host driver to your main MCU will be not required. Disadvantage of this approach is that you will need to program two MCUs (your main MCU and application processor inside CC3220).

Jan

Hi Jan,

I have a question while checking the following URL.
https://www.ti.com/lit/ug/swru455l/swru455l.pdf

It is stated that the CC3120MOD does not support Real time RSSI.

I understood that RSSI information is not included in the received packet information (Radiotap Header).
Is it correct what I understood?

Should STA use another module (ex)CC3130MOD) to check RSSI?

Regards,
Simon

Hi Simon,

I am sorry I am not able answer your question because I don't use transceiver mode regularly.

Please create new thread related to this question.

Jan