16
8-Bit Configurations
8-Bit Data, Single Row, 32 Sample Configurations
An 8 x 32 correlation also requires only 1 HSP45256. To
initialize the correlator, all the reference bits, control bits, the
value of the programmable delay, and the window configuration
must be specified. Table 12 details these settings.
Again, the loading of the reference and mask registers can
be done simultaneously. Due to the programming
initialization, DREF0-7 are used to load the reference data 8-
bits at a time. It will take 32 load pulses each of RLOAD and
CLOAD to load both arrays. Upon completion of the mask
and register loading, TXFR is pulsed low, which transfers the
reference and control data from the preload registers to the
registers that store the active data.
This configuration performs correlation of an 8-bit number
with a 1-bit reference. Each byte out of the correlation array
gives an 8-bit level of confidence that the data corresponds
to the reference. The correlation score is the sum of these
confidence levels.
TABLE 12. REGISTER LOADING FOR 8 X 32 CORRELATOR
WITH BINARY WEIGHTING
A0-2
DCONT0-7
NOTES
001
00001111
1 256-tap correlator; 8 x 32 window configu-
ration, 8-bit data stream; reference register is
loaded from DREF7 for all stages. Correlator
score = (128 x CO7) + (64 x CO3) + (32 x
CO5) + (16 x CO1) + (8 x CO6) + (4 x CO4)
+ (2 x CO2) + CO0.
010
00000000
Offset Register A = 0000000010000.
011
00010000
100
00000000
Programmable Delay = 0.
101
00000000
Offset Register B = 0 (Loading optional in
this mode).
110
00000000
7
6
5
4
3
2
1
0
REF <7>
DATA <7>
REFOUT <0>
DATAOUT <0>
CS = 128CO7+64CO6+32CO5+16CO4+8CO3+4CO2+2CO1+CO0
REFOUT <4>
DATAOUT <4>
REFOUT <3>
DATAOUT <3>
DATA <3>
REFOUT <6>
DATAOUT <6>
REFOUT <5>
DATAOUT <5>
REFOUT <2>
DATAOUT <2>
REFOUT <1>
DATAOUT <1>
DATA <1>
DATA <5>
DATA <6>
DATA <4>
DATA <2>
DATA <0>
REFOUT <7>
DATAOUT <7>
FIGURE 14. 8 BITS, 1 ROW OF 32 TAPS
HSP45256