Uart Interface; Reset And Reload - USR IOT USR-C322 Hardware Manual

USR-C322 Hardware Manual www.usriot.com

2.3. UART Interface

When communicate to MCU with 3.3V, just connecting TXD of module to RXD of MCU and RXD of module to
TXD of MCU.
When communicate to MCU with 5V, switching circuit is necessary.
Switching circuit diagram as follows:
Figure 6 UART interface

2.4. Reset and Reload

nReload: nReload pin can connect to external button or configuration pin. Press button 1s to 3s to enter
simplelink mode, press over 3s to restore factory settings. nReload pin should connect to external 4.7k-10k
Ohm pull-up resistor.
nReset: Resetting the module and taking effect in low level. nReset pin connect to internal 100K Ohm pull-up
resistor to 3.3V. Press over 0.5s and release to reset the device.
Circuit diagram as follows:
Figure 7 Reset and Reload
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