Data Sheet

Datasheet [Page 8]
EMW3072
10
I2C0_SDA
SDIO_INT
UART1_RXD
SPI1_MOSI
GPIO_3
11
I2C0_SCL
UART1_TXD
SPI1_MISO
GPIO_2
12
I2C0_SDA
SDIO_INT
UART1_RXD
SPI1_MOSI
GPIO_3
13
STRAP/SEL1
UART1_CTS
PWM0
SPI2_SCK
GPIO_14
14
MODE_SEL3
ADC7
UART1_CTS
PWM1
SPI2_SCK
GPIO_10
15
SWD
UART0_RXD
PWM7
SPI1_SCK
GPIO_1
16
SWC
UART0_TXD
PWM5
SPI1_CSN
GPIO_0
17
BOOT
UART2_TXD
SPI2_CSN
GPIO_12
18
PAD_SEL
Description:
(1) PIN 17 pin is used by BOOT by default, PIN 3 pin is used by EASYLINK, PIN 21/22 pin is used by debugging log information
output. Please try not to use it in hardware design. If you want to use it, please contact our engineer to confirm.
(2) PIN11/12 pin must be High level while it’s power on, and it can be pull-up by externally connecting with 100k resistance. Please
pay special attention to the design of the circuit.
(3) In order to enable pins, CHIP_EN pulls down the resettable module and then pulls up the resettable module. If not used, it can
remain suspended or pull up 3.3V at 10K.
(4) PIN11/12 can be internal 100k weak pull-up, please allocate related peripheral devices reasonably.
(5) PIN18 can be used to choose PAD mode, which is raised when burning, and floating usually.
(6) Other non-pins can be kept in suspension. It should be noted that IO port is a floating state at startup. This is true from the
beginning of ROM code. It can be pulled up and down in boot code as soon as possible, and the time it takes will be affected by flash.
Therefore, if the module needs to be in the level state determined by module at startup, it needs to be added to the outside that less than
100k resistor pulled up and down to stabilize the level. As shown in the figure below, when the module is started, the level of the IO
port, which is configured to be very low, is changed when the floating state is pulled up by an external 100K resistor.