I have some small automation project whose elements are Arudinos connected using bluetooth modems to communication/command center (raspberry with simple control website). Number of items comes close to bt maximum and i have begun to search for alternatives, that may be able to use higher speeds for some later uses. I have found some new category of devices, the serial to wifi adapters. I have found some devices, but little to no reviews and experiences about using them, so I need help deciding before I buy some of those devices.
1. USR USR-WIFI232-A, price ca. 26usd
I have found documentation file (http://www.tcp232.net/download/USR-WIFI232-X-V4.4_en.pdf
) about this product and was deeply impressed by all the options on paper.
2. USR USR-WIFI232-T, price ca. 13usd
This is low power version of first device. Maybe I have overlooked something, but I could not find why this device costs a half of the first one. It only misses the internal antenna chip.
3. Hi-Link HLK-MO3, price ca. 11usd
Could not find much about it
4. Hi-Link HLK-RM04, price ca. 14usd
Could not find much about it either
5. TLG10UA03 FZ0417, price ca. 13.5usd
I have found some content on youtube in Spanish or Portuguese language.
6. 8devices Carambola 2, price ca. 19eur; with evaluation board 33eur
The device should be able to communicate in both directions, receiving by wifi sending serial and other way around. AP mode is not needed for all current and planned uses, because I will use a dedicated router for that network segment. Wifi security WPA2 is much needed, but as I can tell all of those devices have appropriate security level. I would like to be able to program device without any evaluation board (which as I understand is not possible with Carambola2).
Thankful in advance,