Hardware Reference Design; Hardware Typical Application - Jinan USR IOT Technology USR-WIFI232-A2 User Manual

USR-WIFI232-A2 User Manual http://www.usriot.com

3.5 Hardware Reference Design

3.5.1 Hardware Typical Application

USR-WIFI232-A2 Hardware Typical Application
Figure 10
Notes：
nRST- Module hardware reset signal. Input. Logics "0" effective.
There is 100K Ohm pull-up resister internal up to 3.3V. When module power up or some issue
happened, MCU need assert nRST signal "0" at least 300ms, then set" 1" to keep module fully
reset.
nReady- Module boot up ready signal. Output. Logics "0" effective.
There is 4.7K Ohm pull-up resister internal up to 3.3V. The module will output "0" "or "Palmodic
Signal" after normal boot up. This signal used to judge if module finish boot up and ready for
application or working at normal mode.
nLink- Module WIFI connection indication. Output.
There is 4.7K Ohm pull-up resister internal up to 3.3V. When module connect to AP (STA mode)
or some WiFi STA connect to module (AP mode), the module will output "0". This signal used to
judge if module already at WiFi connection status.
nReload- Module restore to factory default configuration.Input. Logics "0" effective.
User can assert nReload signal "0" more than 3's through button or MCU pin, then release,
module will restore to factory default configuration and re-start boot up process. User need add
4.7K~10K Ohm pull-up resister external the module.
UART_TXD/RXD- UART port data transmit and receive signal.
There is 1K Ohm pull-down resister internal. User can't add pull-up resister at these pins.
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