A Study Of Display Unit For NAVTEX Receiver

As an import part of Global Maritime Distress and Safety System(GMDSS), NAVTEX is the system that broadcasts and automatically receive the marine safety information by means of Narrow Band Direct Printing telex(NBDP) The system uses the frequency of 518kHz to broadcast English marine security information,and it may also use the frequency of 486kHz to broadcast Chinese marine safety information in our country.But currently the NAVTEX receiver in our country can only receive English marine safety information.So it is necessary to design the NAVTEX receiver which can receive Chinese marine safety information.The article "A Study of Display Unit for NAVTEX Receiver" is a part of the project "New Ship Carrier meteorological Information Receiver".This project is to design and realize LCD receiver which can broadcast and receive English/Chinese marine safety information and meteorological fax automatically.And the goal of the article is to design and realize the display unit of the receiver which belongs to the part of human-computer interface by using the ARM embedded system based on the Chinese NAVTEX system.Not only displaying the received information from the master control, but also displaying the active status/ set up process(including rational and artistic design to each menu)/time and finishing settings by pressed key.The article makes the summary analysis to technical characteristic of the Chinese character NAVTEX system,and to do some introduction to the ARM processor LH79525 which uses to design and realize the receiver.It focuses the discussion and research on embedded operating systemμC/OS-Ⅱand embedded graph user systemμC/GUI which uses on the ARM processor.It realizes keyboard's function by using the partial hardware of LH79525 and multi-task scheduling and the execution between keyboard and display in transplanted OSμC/OS-Ⅱ.Most importantly it usesμC/GUI to design and realize the whole display screen.The article takes LCD as display device which is easy to control.It overcomes the special requirement of the printer/printing paper to the environment like temperature, the humidity,the vibration etc.,and it is convenient to view information.Moreover it can highlight the different information use different color or icon which makes great advance on layout and function.