The Application Research Of Information Terminal Based On SEP3203 Microprocessor

The design of the hardware solution in the paper is based on analyzing other design of businesstelephones and the features of SEP3203. The hardware structure of this project is using 16/32 RISCmicroprocessor based on ARM7TDMI as system's core processor and DTMF,FSK chips to implementphonefunction.MemorysystemcontainsNANDFLASH,SDRAM.etc,thereareEthernet,USBandaudiointerfaces. System provides embedded operating system and can use software to realize MP3,recordingfunctions.Focused on the bit reversion and invalid block in NAND FLASH, introduce the reasons why theyoccurred in NAND FLASH. Then we give the common flow chart for resolving invalid block and ECCarithmeticprincipletofinderrorandcorrectonebiterror.Becauseoftheimportanceofthe resolvinginvalidblock,sogivestheprogramwhichhastheresolvinginvalidblockfunction.Finally,wepresenttheactualPCBpictures. Basedonthesepictures,weintroducetheelementspositiononPCB.Functionsandcapabilityofthesystemweretested.Accomplished business telephone has these main parameters: input voltage is 5.10V, electric current is560mA; the system uses 12 MByte memory and consumed about 4.5 MByte SDRAM when system isrunning; When system clock is 70MHz, speech system can work at 29.92KByte/s and 33.98KByte/s forencoding and decoding and MP3 system can decode a fram in 23.82ms. Audio system has been real-time;LCD screen uses about 200ms to display a frame data; when use TCP protocol to transfer data the networkspeed is about 115KByte/s; when use USB to transfer data it have two speed: 135.89 KByte/s and 580KByte/s;FSKdecodingfunctioncandealwithBell202andCCITTV.231200baudrateFSKsignal.