Datasheet

$
2. Pin Definitions
8
XPD_DCDC
I/O
Deep-sleep wakeup (need to be connected to EXT_RSTB);
GPIO16.
9
MTMS
I/O
GPIO14; HSPI_CLK
10
MTDI
I/O
GPIO12; HSPI_MISO
11
VDDPST
P
Digital/IO Power Supply (1.8V ~ 3.3V)
12
MTCK
I/O
GPIO13; HSPI_MOSI; UART0_CTS
13
MTDO
I/O
GPIO15; HSPI_CS; UART0_RTS
14
GPIO2
I/O
UART Tx during flash programming; GPIO2
15
GPIO0
I/O
GPIO0; SPI_CS2
16
GPIO4
I/O
GPIO4
17
VDDPST
P
Digital/IO Power Supply (1.8V ~ 3.3V)
18
SDIO_DATA_2
I/O
Connects to SD_D2 (Series R: 200Ω); SPIHD; HSPIHD; GPIO9.
19
SDIO_DATA_3
I/O
Connects to SD_D3 (Series R: 200Ω); SPIWP; HSPIWP;
GPIO10.
20
SDIO_CMD
I/O
Connects to SD_CMD (Series R: 200Ω); SPI_CS0; GPIO11.
21
SDIO_CLK
I/O
Connects to SD_CLK (Series R: 200Ω); SPI_CLK; GPIO6.
22
SDIO_DATA_0
I/O
Connects to SD_D0 (Series R: 200Ω); SPI_MSIO; GPIO7.
23
SDIO_DATA_1
I/O
Connects to SD_D1 (Series R: 200Ω); SPI_MOSI; GPIO8.
24
GPIO5
I/O
GPIO5
25
U0RXD
I/O
UART Rx during flash programming; GPIO3.
26
U0TXD
I/O
UART Tx during flash progamming; GPIO1; SPI_CS1.
27
XTAL_OUT
I/O
Connects to crystal oscillator output, can be used to provide BT
clock input.
28
XTAL_IN
I/O
Connects to crystal oscillator input.
29
VDDD
P
Analog Power 2.5V ~ 3.6V
30
VDDA
P
Analog Power 2.5V ~ 3.6V
31
RES12K
I
Serial connection with a 12 kΩ resistor and connects to the
ground.
32
EXT_RSTB
I
External reset signal (Low voltage level: Active)
Pin
Name
Type
Function
📖 Note:
GPIO2, GPIO0, and MTDO are configurable on PCB as the 3-bit strapping register that determines the
booting mode and the SDIO timing mode.
Espressif
$ /$6 25
2017.05