private int _I2cRead(byte devAddr, byte length, byte[] data) { int rv; if (i2cMaster.connected == false) { if (_I2cMasterConnect() < 0) { return(-1); } } rv = i2cMaster.ReadRawApi(devAddr, length, data); if (rv < 0) { MessageBox.Show("QSFP+ module no response!!"); _I2cMasterDisconnect(); } else if (rv != length) { MessageBox.Show("Only read " + rv + " not " + length + " byte Error!!"); } return(rv); }