Specifications

3-12 Programming Guide
Remote Data Transfer ESG Family Signal Generators
User File Data Downloads
User File Data Downloads
Option UN8 or UN8/UN9 signal generators accept user file data downloads. After
downloading the data, the user files can be selected as the transmitting data source for the
active digital communications standard. This section contains information that will help
you transfer user file data from a system controller to the signal generator.It explains how
to download user files into the signal generator’s memory catalog and modulate the carrier
signal with them.
In framed mode, user files data will be inserted into the data fields of an existing or
user-defined, custom framed digital modulation format (DECT, PHS, TETRA, custom
user-defined format, etc.).
The instrument’s firmware generates the required framing structure and inserts the data
contained within the user file into the data field(s) of the active format. For more
information, see “User Files as Data Source for Framed Transmission” on page 3-14.
NOTE Unlike downloads to pattern RAM, user files contain “data field” information
only. The control data bits required for files downloaded directly into PRAM
are not required for user file data.
In pattern mode, the user file is modulated as a continuous, unframed stream of data,
according to the modulation type, symbol rate, and filtering associated with the active
digital communications format (DECT, TETRA, PHS, etc.).
When a user file is selected as the data source, the signal generator’s firmware loads
PRAM with the data specified in the user file, and sets the other seven control bits
depending upon the operating mode selected, regardless of whether continuous or framed
transmission is selected. In this manner, user files are mapped into PRAM such that one
user file data bit equals one byte and occupies one address in PRAM.
Bit Memory versus Binary Memory
You can download user files to either the bit memory or binary memory catalog.
The bit memory catalog accepts data in any integer number of bits, up to the maximum
available memory in the bit memory catalog (approximately 1 Mbit). The data length in
bytes for files downloaded to the bit memory catalog is equal to the number of significant
bits plus seven, divided by eight, then rounded down to the nearest integer. You must have
enough bytes to contain the bits you specify. If the number of bits is not a multiple of 8, the
least significant bits of the last byte will be ignored.
The bit memory catalog provides more versatility and is the preferred memory catalog for
user file downloads.
The binary memory catalog requires data formatted in 8-bit bytes. Files stored or
downloaded to the binary catalog are converted to bit files prior to editing in the bit file
editor. Afterward, these modified files from the binary memory catalog are stored in the bit
memory catalog as bit files.