visual defects
8.Results The data of FFA of AION 38 cases 42 eyes and PION 3 cases 5 eyes showed arm-retinal circulatory time of 32 eyes were delayed. Choroidal filling time of 12 eyes were absent near optic disc. All or a part of optic disc had postponed or absent fluorescence filling with the corresponding visual field defects.
9.This paper analysis the characteristics of the serial communication control unit of Visual Basic,and uses the AscB()and BYTE variable to handle the data. This method remedies the defects of STRING variable,which can only process the characters whose ASCII codes are between 00 - 7FH, and realizes the communication between a PC and a single-chipmicroc omputer under Windows environment.

