Radio Shack TRS-80 PC-3 Owner's Manual page 104

filename and password.
It the PC-3 Computer is in PROgram or RUN mode, program memory is loaded to the tape. When the PC-3 Computer is in the
ReSerVe mode, reserve memory is loaded.
Examples
CSAVE "PR03", "SECRET" Saves the programs now in memory onto the tape under the name 'PR03', protected with the
password 'SECRET'.
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