Figure 4-4 Structure of USB functions
4.5.4 LCD&Touchscreen Driver Control
CPU realizes the functions of LCD drive control, reading touch screen data,
transforming data transfer protocol.
Figure 4-5 Graph of LCD/touchscreen drive control
4.5.5 Serial Port Communication
The COM0 of CPU board uses RS232 level translator to translate the level, realizing
the serial port communication with PC. The communication between COM3 and
recorder is realized through the level translation between LVTTL and TTL.
Figure 4-6 Graph of serial port communication