Motorola MPC860 PowerQUICC User Manual page 926

Part V. The Communications Processor Module
Address Name
Hword 1 I Number of iterations
Hword 2 K Number_of_taps - 1
Hword 3 CBASE Filter coefÞcient vector base address
Hword 4 M Input buffer_size - 1. The minimum input buffer size is 8 (4 samples).
Hword 5 XYPTR Pointer to a structure composed of the input buffer pointer and the output buffer pointer
Hword 6 N Output buffer_size - 1. The minimum output buffer size is 8 (2 outputs).
Hword 7 Ñ Reserved
36.11.2.3 FIR2 Applications
The FIR2 is used for Tx and Rx Þlters. For example, the partial FD shown in Figure 36-13
can be used to implement a Tx Þlter.
S Ñ
Offset + 0 S 0
Offset + 2
36.11.3 FIR3ÐComplex C, Complex X, and Real/Complex Y
Using the values provided in the parameter packet, the FIR3 implements a basic FIR Þlter,
shown in Figure 36-14, with K complex coefÞcients, complex input samples, and real or
complex output. The input data is in a circular buffer with size (M+1) and the output data
is in a circular buffer with size (N+1).
36-12
Table 36-10. FIR2 Parameter Packet
W I Ñ IALL
W I 0 0
I=3 (Three Iterations)
Figure 36-13. FIR2 Filter Example
MPC860 PowerQUICC UserÕs Manual
Description
INDEX PC Ñ Ñ
01 0 0 0
OPCODE
00010
MOTOROLA