Well spotted. ~1000 bytes I think.

Add print statements to narrow down what happens just before Might be unintended recursion.

Not an actual test, but using them in my house, 50 feet (15 meters) maybe. These are the printed circuit antenna devices. I think they hear better than they transmit. At one point I tried reducing the Tx power and could not connect via the house router, so I left the Tx power at the max.

m_csv is uninitialized for that code path; you should at least set it to null. Something shortly after the return may be trying to use it.
Is there a destructor? or a copy constructor? Do they try to free the memory m_csv points to?

I'm using this with good results otaPartition = esp_ota_get_next_update_partition(NULL); rc = esp_ota_begin(otaPartition, OTA_SIZE_UNKNOWN, &otaHandle); // we know the size, but unknown erases all then, in the receive loop, rc = esp_ota_write(otaHandle, buf, received); finally if(!badUpdate){ rc = e...

I think the esp's default SNTP sync interval is an hour. The clocks could easily drift apart 100ms in an hour.

https://en.wikipedia.org/wiki/Network_T ... ol#History was a fun read.

Use a hidden field in the form.
https://www.w3schools.com/tags/att_inpu ... hidden.asp

Thanks! The largest free block seems more useful to report than what I'm currently doing.

Or maybe one of these esp_get_free_heap_size() esp_get_free_internal_heap_size() esp_get_minimum_free_heap_size() I found the last one (minimum free heap) most useful. I think it tracks over time the smallest available heap; I've seen it drop to 50KB if I use the web server aggressively but it is us...

I don't call sntp_sync_time directly. And I don't have my own function by that name. All I do is this: sntp_setoperatingmode(SNTP_OPMODE_POLL); sntp_setservername(0, sClockState.cfgSntpUrl[0] ); // "pool.ntp.org" sntp_set_time_sync_notification_cb(time_sync_notification_cb); sntp_init(); I get the c...