Does anyone got WROOM antenna radiation pattern graph?
Which way does it radiate most?
Search found 54 matches
- Thu Mar 23, 2017 8:33 pm
- Forum: General Discussion
- Topic: WROOM antenna radiation pattern
- Replies: 2
- Views: 6682
- Thu Mar 23, 2017 11:57 am
- Forum: General Discussion
- Topic: I2C: protection against connection (lines) problems
- Replies: 9
- Views: 14201
- Mon Mar 20, 2017 8:09 pm
- Forum: General Discussion
- Topic: Powering my esp32 projects
- Replies: 6
- Views: 22044
Re: Powering my esp32 projects
Maybe a joule thief
You can use your 0.2Ah battery. Value 0.2A (and even more) I wrote before is true when everything is on. Just remember about it writing a code, switch into powersave mode as often as it is possible, use pullups 10k and do not use a wifi too often
You can use your 0.2Ah battery. Value 0.2A (and even more) I wrote before is true when everything is on. Just remember about it writing a code, switch into powersave mode as often as it is possible, use pullups 10k and do not use a wifi too often
- Sun Mar 19, 2017 11:07 am
- Forum: General Discussion
- Topic: I2C: protection against connection (lines) problems
- Replies: 9
- Views: 14201
I2C: protection against connection (lines) problems
Each time, when I2C's lines SCL or SDL stops connect (eg. I am unplugging it), i2c_master_cmd_begin returns ESP_FAIL or ESP_ERR_TIMEOUT . If ESP_ERR_TIMEOUT is returned, I2C wont work anymore - after replugging disconnected pins, result is still ESP_ERR_TIMEOUT . How to protect it to recover after d...
- Sun Mar 19, 2017 9:25 am
- Forum: General Discussion
- Topic: Powering my esp32 projects
- Replies: 6
- Views: 22044
Re: Powering my esp32 projects
5V power supply would damage esp.
Esp if you're not too frugal (wifi on, low value resistors for pullups) needs about 0.2A and your battery will die in 1 hour.
Esp if you're not too frugal (wifi on, low value resistors for pullups) needs about 0.2A and your battery will die in 1 hour.
- Sat Mar 18, 2017 10:59 pm
- Forum: General Discussion
- Topic: Hardware timer
- Replies: 1
- Views: 4483
Hardware timer
CPU freq is 240MHz. Timer configuration is like the one below. I check if timer_val (from timer_get_counter_value) is larger than 36621 (36621 * 0xffff = 2 399 957 235). I believed it was 10seconds, but it seems to take more than 31 secs; why? Are some timers used by WiFi or interface's (I2C, SPI, S...
- Wed Mar 15, 2017 8:02 pm
- Forum: General Discussion
- Topic: RTC hold capacitor
- Replies: 1
- Views: 3735
RTC hold capacitor
I would use WROOM module, so VDD3P3_RTC is not available.
How can I hold RTC when main power is down and do not drain its energy too fast - how to programmatically switch off everything but RTC, what current is needed than?
How can I hold RTC when main power is down and do not drain its energy too fast - how to programmatically switch off everything but RTC, what current is needed than?
- Wed Mar 15, 2017 7:44 pm
- Forum: General Discussion
- Topic: Where is fourth SPI
- Replies: 5
- Views: 8987
Where is fourth SPI
I use esp-wroom-32 module (so flash is build in). I need sd card interface and two more independent SPI interfaces.
I see SPICLK - SCK/CLK, HSPICLK - IO14, VSPICLK - IO18. Where is last, fourth one clk pin?
What about its speed? Which is best for TFT Display connection?
I see SPICLK - SCK/CLK, HSPICLK - IO14, VSPICLK - IO18. Where is last, fourth one clk pin?
What about its speed? Which is best for TFT Display connection?
- Thu Feb 23, 2017 10:58 pm
- Forum: General Discussion
- Topic: SDCard card detect and write protect pins
- Replies: 6
- Views: 9494
SDCard card detect and write protect pins
How to use gpio_cd and gpio_wp?
I am unable to find it anywhere else but inside sdmmc_host_init_slot.
I am unable to find it anywhere else but inside sdmmc_host_init_slot.
- Sun Dec 18, 2016 9:59 pm
- Forum: General Discussion
- Topic: Allocating more memory result in bulk errors
- Replies: 2
- Views: 6322
Allocating more memory result in bulk errors
Working with WiFi, whenever I alloc any buffer larger than ~64bytes, my code crashes, but whats important I am unable to detect any accurate place where it does. Like there would be no more memory and when some background things for WiFi receive some packets, alloc space for them, the code stops: ch...