Communication Processor Module
16-38 MPC823e REFERENCE MANUAL MOTOROLA
DSP
COMMUNICATION
16
PROCESSOR MODULE
/* Buffer Descriptors */
typedef struct dsp_fd {
unsigned short status;
unsigned short parameter[7];
} DSP_FD;
#define WRAP 0x2000 /* wrap bit */
#define INTR 0x1000 /* interrupt on completion */
/* define for function opcodes */
#define FIR_2 0x0102 /* FIR2 filter */
#define MOD 0x0008 /* Modulation function opcode */
/* Initialize a static fd table for 2 functions */
DSP_FD filters[2]= {
{ FIR_2,P11,P12, , P17}
,{(WRAP | INTR | MOD),P21,P22, , P27}
};
void main()
{
/* Setup FD chain pointer */
DSP2_Base. Fdbase = filters;
*
/* issue command to CPM to start processing the fd chain */
issue_command( START_FD );
*
*
*
}
16.3.4 DSP On-Chip Library Functions
The DSP library is an easy way to implement DSP functions. It consists of the following
functions:
• FIR1—Finite impulse response 1
• FIR2—Finite impulse response 2
• FIR3—Finite impulse response 3
• FIR5—Finite impulse response 5
• FIR6—Finite impulse response 6
• IIR—Infinite impulse response
• MOD—Modulation
• DEMOD—Demodulation
• LMS1—Least mean squared 1
• LMS2—Least mean squared 2
• WADD—Weighted vector addition