Search found 9 matches

by ry1234
Wed Feb 08, 2017 5:09 pm
Forum: General Discussion
Topic: wifi scan in non-blocking mode
Replies: 5
Views: 10537

Re: wifi scan in non-blocking mode

Hi,

Another piece of information: the esp_wifi_scan_start() API takes 200 msec to return, for a single Wifi channel:

wifi_scan_config_t cfg = {NULL, NULL, 1, false};
ESP_ERROR_CHECK( esp_wifi_scan_start(&cfg, true));

So I suspect it is performing a passive scan (?)
by ry1234
Wed Feb 08, 2017 5:07 pm
Forum: General Discussion
Topic: wifi scan in non-blocking mode
Replies: 5
Views: 10537

Re: wifi scan in non-blocking mode

Hi Neil,
Passive scanning is where the client listens to the beacon broadcasts (typical beacon interval is 100 msec).
Active scanning is where the client transmits a probe request and waits for a probe response from all SSIDs that received the request.
by ry1234
Wed Feb 08, 2017 4:03 pm
Forum: General Discussion
Topic: wifi scan in non-blocking mode
Replies: 5
Views: 10537

Re: wifi scan in non-blocking mode

Thanks for that.

Does the wifi_scan_start() api initiate an active scan or a passive scan (or both)? I would like to limit to active scan only, couldn't find a way so far to control the behavior beyond a brief mention in the data sheet.

Thanks!
by ry1234
Sat Feb 04, 2017 3:42 am
Forum: General Discussion
Topic: wifi scan in non-blocking mode
Replies: 5
Views: 10537

wifi scan in non-blocking mode

Hi

I would like to use esp_wifi_scan_start() in non-blocking mode; is there an API or register that allows to check if the scan has completed?

Thanks!
by ry1234
Fri Feb 03, 2017 2:46 am
Forum: General Discussion
Topic: HW Timer ISR keeps triggering
Replies: 3
Views: 8146

Re: HW Timer ISR keeps triggering

Check the example for what to do inside the isr https://github.com/espressif/esp-idf/blob/a14bef8f8a854be557d40c893af513f963e1cac4/examples/peripherals/timer_group/main/timer_group.c#L116 I think minimum is TIMERG0.int_clr_timers.t1 = 1; TIMERG0.hw_timer[timer_idx].config.alarm_en = 1; This did the...
by ry1234
Thu Feb 02, 2017 4:01 pm
Forum: General Discussion
Topic: HW Timer ISR keeps triggering
Replies: 3
Views: 8146

HW Timer ISR keeps triggering

Hi, I am trying to configure the HW timer to trigger an ISR every 10 seconds. What I see instead is that the ISR gets triggered for the first time indeed after 10 seconds, but then keep getting triggered continuously until I get an 'interrupt wdt timeout' exception. Can anyone suggest what I am doin...
by ry1234
Fri Dec 23, 2016 2:48 am
Forum: ESP-IDF
Topic: Validate Hibernate Mode into ESP32
Replies: 14
Views: 29672

Re: Validate Hibernate Mode into ESP32

One more note: it is possible to power down RTC fast memory (it just is kept powered on by default). If you do so with the current chip revision, it will resume from deep sleep but will experience a watchdog reset and then proceed to normal boot. This extra time spent waiting for wdt reset may canc...
by ry1234
Sun Dec 18, 2016 9:19 pm
Forum: General Discussion
Topic: flashing from windows machine
Replies: 1
Views: 8129

flashing from windows machine

Hi, This is a novice question, but I can't seem to figure it out. I followed the Windows tool chain setup instructions and built a sample application. I am now ready to flash it to the DevC Kit board. When connected to my laptop, it shows up as COM27. In 'make menuconfig' I thus set the serial port ...
by ry1234
Sun Dec 18, 2016 6:21 pm
Forum: General Discussion
Topic: deep sleep and start time
Replies: 2
Views: 5571

deep sleep and start time

Hi, A few questions about the time it should take to go back to running code after ESP32 is in deep sleep - - Is it correct that every time ESP32 recovers from deep sleep, the image has to be copied from flash to RAM (meaning, code is not executed directly from flash)? - If so, how long does it take...