GC2011A Datasheet, PDF (16/50 Pages) Texas Instruments – 3.3V DIGITAL FILTER CHIP

GC2011A 3.3V DIGITAL FILTER CHIP
SLWS129A
By triggering on the TC strobe the user can guarantee that the snapshots are spaced by a known number of
samples. For example, the user can program the chip to capture blocks of 512 samples every 2²⁰ clocks. The blocks
can then be coherently combined to calculate accurate spectral information.
Once the snapshot has been triggered, the chip clears the START control bit. When the snapshot is finished
the chip will set the A_DONE or B_DONE bits in SNAP_REGC. NOTE that the delay from START being cleared to the
DONE bits being set can be up to 8192 clocks when the rate is every fourth clock and the trigger delay is set to 15.
The user accesses the snapshot as 256 16 bit words using addresses 256 to 511 in the chip’s control address
space. If the samples were stored as bytes, the results can either be read as two byte words, or be read as sign
extended bytes. If the user is reading bytes, then a control bit is used to select the upper or lower byte. The snapshot
memory is read-only by the user.
Texas Instruments Incorporated
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