NXP Semiconductors MPC5644A, Reference Manual, Page: 1195 / 1735

Decimation Filter
MPC5644A Microcontroller Reference Manual, Rev. 6
Freescale Semiconductor 1195
26.4.2.7 Decimation Filter Coefficient n Register (DECFILTER_COEFn)
26.4.2.8 Decimation Filter TAPn Register (DECFILTER_TAPn)
Address: DECFILTE 0x020–0x040 Access: User read/write
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
R 8{COEFn[23]}
COEFn[23:16]
W
Reset 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31
R
COEFn[15:0]
W
Reset 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Figure 26-8. Decimation Filter Coefficient n Register (DECFILTER_COEFn)
Table 26-20. DECFILTER_COEFn Register Field Descriptions
Field Description
0–7
8–31
COEFn[23:0]
Coefficient n field
The COEFn[23:0] bit fields are the digital filter coefficients registers. The coefficients are
fractional signed values in two’s complement format, in the range (-1

coef < 1).
Note: Reads to this register are sign-extended, meaning the coefficient’s sign bit is copied to all
eight most significant register bits.Writing to these fields when BSY = 1 is not allowed.
Address: DECFILTE 0x078–0x094 Access: User read only
0 1 2 3
4
5 6 7 8 9 10 11 12 13 14 15
R 8{TAPn[23]} TAPn[23:16]
W
Reset 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31
R TAPn[15:0]
W
Reset 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Figure 26-9. Decimation Filter TAPn Register (DECFILTER_TAPn)
Table 26-21. DECFILTER_TAPn Register Field Descriptions
Field Description
8–31
TAPn[23:0]
TAPn Register
The read-only TAPn[23:0] bit fields shows the contents of the digital filter tap registers, as
fractional signed values in two’s complement format, in the range (-1

coef < 1).