Upgraded ESP-01S ESP8266 Serial WIFI Wireless Module Wireless Transceiver
- ESP01S ESP8266-01S (stronger antenna signal compared to esp01)
- 1MB flash (from 512M)
- Integrated WEP, TKIP, AES, and WAPI engines. 802.11 b/g/n
- Wake up and transmit packets in 2ms
- standby power consumption of 1.0mW (DTIM3)

Feature:
- Power down leakage current <10uA
- Integrated low power 32-bit CPU could be used as application processor

------
|ANT.|
|    |
|    |
|8765|
|1234|
------

1|tx|
2|ch_pd|1-enable
3|rst|0-reset
4|vcc|3.3v
5|rx|
6|gpio0|0-flash mode (def), 1-uart mode (prog)
7|gpio2|gpio
8|gnd|