Database subsystem overview The database describes spacecraft commands and spacecraft telemetry. Each spacecraft command is described in terms of the command mnemonic, zero or more command fields, and submnemonic values. The ITOS database does not require any commercial database package. The ITOS also includes tools for viewing the database over the World Wide Web. The current value table contains the most recent value for each mnemonic.
Most ITOS components obtain mnemonic values by polling the current value table.
An alternative mechanism, where the component registers interesting mnemonics and gets notified every time a new value arrives, is also available. Wraps frames, developed for code 521. The telemetry subsytem uses either the TCP or UDP protocol. STOL overview STOL is the primary interface for controlling the ITOS software. STOL can also access telemetry values and can perform complex arithmetic using those values.