WinSSD is a full-featured synchronous/asynchronous diagnostic utility for Microsoft Windows operating systems. For asynchronous serial devices, WinSSD allows the user to modify the default UART parameters, perform external loopback tests, toggle modem control signals, perform simple BERT tests and includes terminal mode emulation.

When used with a Sealevel synchronous serial adapter, the user has full control over electrical interface, framing method, RSET and TSET source, transmitter and receiver bitrate, oscillator frequency, CRC, preamble, clock encoding, sync character and more.