Agilent Technologies VXI E1439 - Manual (Page 109)

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Agilent E1439 Programmer's Reference
Functions listed alphabetically
The units of epochSize are always in bytes and this value must be divisible by 4, with a minimum
value of 8 to a maximum value of 4,294,967,292 bytes.
Note
For maximum compatibility with other fiber optic components, values divisible by 8 are
recommended.
When the module is being used in a fiber append chain, epochSize must be set equal to blocksize
(in bytes). Since the function AGE1439_DATA_BLOCKSIZE sets the blocksize in samples, the
following table can be used to compute blocksize in bytes.
Note
You may set blocksize and epochSize independently for the other fiberMode settings.
epochSizePtr points to the current value of epochSize
headerEnable controls whether or not epoch headers are generated.
AGE1439_HEADER_ON enables epoch header generation
AGE1439_HEADER_OFF disables epoch header is generation.
The default setting is off. Epoch headers are enabled only when epoch generation is enabled.
Otherwise, epoch header settings are silently accepted. The epoch header setting must match the
configuration of the optical receiver.
headerEnablePtr points to the current value of headerEnable
headerValue sets the value of the first 32 bits of the epoch header.
AGE1439_HEADER_VALUE_MIN selects the minimum value for the epoch header.
AGE1439_HEADER_VALUE_MAX selects the maximum value for the epoch header.
AGE1439_HEADER_INDEX_MASK is used for setting the value of the headerIndex field.
AGE1439_HEADER_INCR_MIN selects the minimum value for the incrementCount.
AGE1439_HEADER_INCR_MAX selects the maximum value for the incrementCount.
Epoch headers are 64 bits long. Of these, the last 32 bits are not used and set to zero. The first 32
bits are available and can be set by the user. The 10 least significant bits of the 32 non-zero bits
contain a value that can be used by the optical receiver to direct where to route and/or how to
process the associated epoch data. These 10 bits are called the headerIndex and can be set from a
value of 0 to 1023. In addition the headerIndex can be sequentially incremented by 1 each time it
is transmitted. The number of increments that are applied before returning to the original value is
programmable by the user.
The headerValue sets the value of all 32 non-zero bits of epoch header, including the 10 least
significant bits that comprise the headerIndex bit field. The default headerValue is 0 and the
maximum value is (2^32 -1).
data type resolution bytes per sample
real 12 2
complex 12 4
real 24 4
complex 24 8