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B WT20C Qilin double swing handheld laser cleaning system user
2.4 human-computer interface HMI
The HMI interface is a DB9 black plug through which the motherboard supplies and
communicates to the HMI,
Figure 2.4 HMI, schematic diagram
Table 2.4 defines the HMI interface.
pin
signal
defi
niti
on
expl
ain
1
24V Power supply
HMI supply electricity
output, 500 mA
2
GND
Power supply output Power reference
ground
3
T XD
The sender of the Serial port communication with the
HMI
TXD signal
4
RXD
The receiving end Serial port communication with the
of the HMI
RXD signal
2.5, the laser decoding interface
port.
LASER RS232 The interface is the board card and the laser communication
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