venu 0 Posted September 24, 2014 Share Posted September 24, 2014 Hi All, I just started using cc3200 launch pad. I could get a external LED blink from webserver running on cc3200. I used SimpleWebServerWifi example to achieve it. Now I wanted to power the launch pad using 2 AA batteries. I could power it as per instructions, but it is not lasting more than 1 hour. Can someone tell me how to enable power saving mode? I want to wakeup only GPIO pins after webserver receives any request. Please help me. Thanks Venu Quote Link to post Share on other sites
spirilis 1,265 Posted September 24, 2014 Share Posted September 24, 2014 That's not really happening yet. I'm also not sure you will ever expect to see good battery life from these MCUs on two AA batteries while having the *webserver* running continuously... I think TI's "Runs on 2 AA's for a year!" claim is for a transmit-only device that wakes up once in a blue moon to send data to the cloud. Running a webserver on the chip, even if you offload it to the WiFi network processor's built-in webserver (which you aren't doing here; Energia support for that is also forthcoming), is a power-hungry use of the chip because it keeps the WiFi subsystem spun up all the time so it's available for connections. Low-power support for sleep(), sleepSeconds() and suspend() in Energia is in place on MSP430 and the strawman functions are there for Tiva/Stellaris (not actually enabling low-power mode yet), but not for CC3200 yet ... There's a lot of work yet to be done for that one. Quote Link to post Share on other sites
venu 0 Posted September 24, 2014 Author Share Posted September 24, 2014 Thanks a lot Spirilis for the explanation. Got it Does the hardware in CC3200 supports it? By looking at power modes in CC3200 document, i thought i can keep the MCU in hibernate mode and keep the network processor as active mode. But as you said, webserver itself may consume lot of power. I will explain my application, can you please suggest right way to do it. I want to rotate a stepper motor wirelessly from mobile or Raspberry pi. Mostly it will be a very small rotation and it is controlled very rarely may be once in a day. I want to power it using 2 or 4 AA batteries. I am fine using any technology, all i want some wireless connection between my raspberry pi and the board. I was thinking of using some bluetooth low energy module, then i saw CC3200 and thought wifi is easy to use Can you please suggest any board, which i can use for this application. Thanks in advance. -Venu Quote Link to post Share on other sites
chicken 630 Posted September 24, 2014 Share Posted September 24, 2014 First step would be to specify what latency is acceptable for your use case. A common pattern for applications that can live with high latency (i.e. long response times) is for the remote device to periodically check a server for updates. E.g. every 10 seconds the CC3200 could wake up, connect to WiFi and check a web service running on the RasPi for an updated stepper position, if required rotate the stepper, then go to sleep again. venu 1 Quote Link to post Share on other sites
spirilis 1,265 Posted September 24, 2014 Share Posted September 24, 2014 Yeah, perhaps once we get real low power modes working in Energia this would be an appropriate use of the CC3200. WiFi is a nice easy way to do things like this IMO. Just power-hungry when it's active. venu 1 Quote Link to post Share on other sites
venu 0 Posted September 24, 2014 Author Share Posted September 24, 2014 Thanks chicken for your input. 10 seconds latency is fine with me. I can do that, every 10 seconds check with raspberry pi webserver whether it has any input and i can interact with raspberry pi webserver to issue the command. Do you have any example hibernate code? As spirilis was saying, the Energia is not ready for this. Do I need to use TI CCS do to this? Can you please suggest. Thanks Venu Quote Link to post Share on other sites
chicken 630 Posted September 24, 2014 Share Posted September 24, 2014 I haven't played much with the CC3200, so no practical advice from me. There are some examples on TI's website: http://processors.wiki.ti.com/index.php/CC32xx_SDK_Sample_Applications e.g. this one looks like a good start to figure out the basics: http://processors.wiki.ti.com/index.php/CC32xx_Sleep-DeepSleep_Application @@spirilis probably can comment what to watch for when trying to do this with Energia instead of CCS. venu 1 Quote Link to post Share on other sites
spirilis 1,265 Posted September 24, 2014 Share Posted September 24, 2014 You can probably get started with CCS and one of the FreeRTOS or TI-RTOS examples. I haven't used those myself though so YMMV. It will be a learning experience I'm sure... Sent from my Galaxy Note II with Tapatalk 4 venu 1 Quote Link to post Share on other sites
BigG 1 Posted October 24, 2014 Share Posted October 24, 2014 Low-power support for sleep(), sleepSeconds() and suspend() in Energia is in place on MSP430 and the strawman functions are there for Tiva/Stellaris (not actually enabling low-power mode yet), but not for CC3200 yet ... There's a lot of work yet to be done for that one. Any status update on the cc3200 low power mode/ sleep functionality Quote Link to post Share on other sites
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