GIGALIGHT’s 400G QSFP-DD optical transceiver checker can be used to test optical transceivers, AOC and DAC. The checker can read the internal memory EEPROM of the modules and display details of the EEPROM (such as the Part Number, Vendor Name, description and range.), monitor all DDMinformation. In addition it can measure the power of the module.The QSFP DD Checker combines the Serial Pattern Generator, Bit Error Rate Analyzer. It provides common transmission rate for 8x25Gbps NRZ and 8×26.5625GBd PAM4.The friendly graphic user interface (GUI) provides clear monitoring for bit error rate, bit errorcounter, time, status, power of the module, selection of data rate and PRBS pattern.