NXP Semiconductors MPC5644A, Reference Manual, Page: 1199 / 1735

Decimation Filter
MPC5644A Microcontroller Reference Manual, Rev. 6
Freescale Semiconductor 1199
NOTE
If the DEFILTER_MXCR bit SSAT = 1, the integration sum is saturated, so
that if the accumulation overflows DECFILTER_CINTVAL holds the value
0xFFFFFFFF for absolute integration (SSIG = 0), or values 0x7FFFFFFF
(positive saturation) and 0x80000000 (negative saturation) for signaled
integration (SSIG = 1).
If SSAT = 0, DECFILTER_FINTVAL holds the integration sum modulo 2
17
(considering the 15-bit fractional part).
NOTE
A read on this register automatically commands an update of the register
DECFILTER_CINTCNT.
26.4.2.13 Decimation Filter Current Integration Count Value Register
(DECFILTER_CINTCNT)
26.4.3 Decimation Filter Memory Map for Parallel Side Interface
The Decimation Filter exchanges data with the master block through the PSI. The master block sends data
to the input buffers and reads data from the output buffers of the filter. To implement this exchange, only
a single register is required as described in
Table 26-27 , therefore the PSI address is ignored.
Address: DECFILTE 0x0EC Access: User read only
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
R COUNT[31:16]
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 COUNT[15:0]
W
Reset 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Figure 26-14. Decimation Filter Current Integration Count Value Register (DECFILTER_CINTCNT)
Table 26-26. DECFILTER_CINTCNT Register Field Descriptions
Field Description
0–31
COUNT[31:0]
Integration Count Value. The COUNT field holds the count of filtered outputs integrated. The
value is updated only when register DECFILTER_CINTVAL is read, to keep the coherency
between the integration and count values.
Table 26-27. Parallel side interface memory map for decfilter data exchange
Decimation filter address Description Access
0x0
DECFILTER_IOB - Decimation Filter
1
input/output Registers
1
The input registers are addressed for write only and output registers are addressed for read only.
R/W