Set Extended Port - WiT WT901B User Manual

2.4.11

Set Extended Port

The WT901B module has 4 multiple function extended ports, which can be set
to different functions according to the need. Set extended port only when the
module connects to the PC software successfully.
The extended port supports analog input mode, digital input mode, digital
output mode, PWM output mode. D1 port also supports GPSRX mode, port state
by default is analog input mode.
The port status packet in which the module exports contains the status
information of the extended port. In different modes, the port state data
DxStatus has the following meanings:
Mode
Analog input mode
Digital input mode
Digital high level output mode
Digital low level output mode
PWM output mode
CLR（D1）
Analog input mode is used to measure the analog voltage on the port, such as
a potentiometer or a sensor, etc.
The formula is as follows:
U=DxStatus/4096*U
Uvcc is the power supply voltage of the module, because the module has LDO if
the module power supply voltage is greater than 3.5V, Uvcc is 3.3V. If the
module supply voltage is less than 3.5V, Uvcc equal to the supply voltage minus
0.2V.
WT901B | manual v0707 | http://wiki.wit-motion.com/english
vcc
Implication
Analog voltage
Port high and low level state
Port output state
Port output state
PWM high level width
The XY relative attitude 0
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