Try something like this
Code:
        CONT con $20
        GP_Port con 0
        LAT_Port con 2
        IODir con 6
        Register var Byte

        Register=IODir        
        i2cwrite idata,iclock, CONT, register,[0,0] ' set all i/o to output
        
        Register=GP_Port 
        i2cwrite idata,iclock, CONT, register,[255,255] ' set all i/o to high
        
        Register=LAT_Port 
        i2cwrite idata,iclock, CONT, register,[255,255] ' set all i/o to high