Справочник Пользователя для High-Flying Electronics Technology Co. Ltd HF-A11X
HF-A11x V3.1 User Manual
Shanghai High-Flying Electronics Technology Co., Ltd
www.hi-flying.com
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User can add RS-232 chipset on user board and convert the signal to RS-232 voltage to
communicate with outside equipment or sensors. HF-A11x modules UART interface include 4
general signals: TXD/RXD/RTS/CTS. The hardware reference design with RS-232 chipset as
following:
communicate with outside equipment or sensors. HF-A11x modules UART interface include 4
general signals: TXD/RXD/RTS/CTS. The hardware reference design with RS-232 chipset as
following:
Figure 10. UART Interface Reference Design
Notes: TXD pin is also hardware configuration pin internal module. So this pin MUST pull-down
during module power up. HF0A11x modules provide internal pull-down resister, user can’t add
pull-up/pull-down resister on user board, which may cause module can’t work.
during module power up. HF0A11x modules provide internal pull-down resister, user can’t add
pull-up/pull-down resister on user board, which may cause module can’t work.
1.3.4. Power
Interface
HF-A11x module support single +3.3V power supply. The peak current shall about 350mA and
normal WiFi working current shall about 200mA. The power save (WiFi OFF) mode will about
100mA
normal WiFi working current shall about 200mA. The power save (WiFi OFF) mode will about
100mA
Decoupling at power pin suggested, At least one 100uF and one 10uF capacitor required at user
board and put near module power input pin will increase the reliability and performance.
board and put near module power input pin will increase the reliability and performance.