Programming instructions

Downloading and Using Files
User File Data Downloads
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3. Bit length must be a multiple of 8 (binary downloads only).
SCPI specifies data in 8-bit bytes, and the binary memory stores data in 8-bit bytes.
If the length (in bits) of the original data pattern is not a multiple of 8, you may need to:
• add additional bits to complete the ASCII character,
• replicate the data pattern without discontinuity until the total length is a multiple of 8
bits,
• truncate and discard bits until you reach a string length that is a multiple of 8, or
• use a bit file and download to bit memory instead.
Data Limitations
Download size limitations are directly proportional to the available memory space and the
signal generator’s pattern RAM size (Option 001= 1 Mbyte, Option 002 = 4 Mbyte). To
determine the maximum user file size, you must consider the following:
• framing overhead
• pattern RAM size (1 Mbyte or 8 Mbyte)
• available memory
You may have to delete files from memory before downloading larger files.
Data Volatility
The signal generator provides two data storage areas: volatile waveform memory (WFM1) and
non-volatile memory (NVWFM). Data stored in volatile waveform memory cannot be
recovered if it is overwritten or if the power is cycled. Data stored in non-volatile memory,
however, remains until you delete the file. The Option 005 signal generator’s hard disk
provides 6 Gsamples of non-volatile storage. Signal generators without Option 005 provide 3
Msamples of non-volatile storage.
NOTE References to pattern RAM (PRAM) are for descriptive purposes only. PRAM
equates to volatile waveform memory (WFM1).