Applications - Geeetech ESP8266 Instruction

80MHZ, with its upper limit as 160MHZ. ESP8266 uses the external SPI Flash to
store user program, with the memory of 1MB. Based on an external crystal, the
crystal oscillator of ESP8266 could generate Radio Frequency clock to drive the
mixer to down-convert the radio frequency signal and transform it as digital signal.
The orthogonal baseband signal would be up-scaled to 2.4GHz. ESP8266 supports
TCP/IP protocol, 802.11 b/g/n/e/I WLAN MAC protocol and the Wi-Fi Direct
standard. The two universal asynchronous receiver transmitters of the hardware could
communicate with the microcontroller in a convenient way.
The pin assignments as shown in Figure 1-1
Pin Name
1 GND
2 CHIP_EN
3 RST
4 RXD
5 TXD
6 GPIO0
7 GPIO2
8 3.3V

1.4 Applications

ESP 8266 WiFi module can be apply to different fields, such as 3D printer,
Figure 2. Interface Definition
Type
P
Chip Enable Terminal:The chip works normally at
I/O
the high level, and closes at the low level with
low current 。
I/O External reset signal （works normally at low level）
I/O
The RX pin of UART，the
I/O
The TX pin of UART，the
FLASH start at the high level; System upgrade at the low
I/O
level (able to upgrade internal firmware via the serial
port)
I/O
P
2
Function
Ground wire
TX pin of external circuit
RX pin of external circuit
Digital power supply 3.3V