AN2254 Freescale Semiconductor / Motorola, AN2254 Datasheet - Page 14

• Manufacturer Part Number: AN2254
• Description: Scrambling Code Generation for WCDMA
• Manufacturer: Freescale Semiconductor / Motorola

Software Implementation on the StarCore SC140/SC1400 Cores
14
3.
4.
5.
6.
Read the I and Q, input signal data from memory, 1-word sample at a time.
Perform the scrambling of the input data signal, according to Equation 16.
Store the I-Q/code interleaved complex scrambled signal into memory.
END mainloop.
Scrambling Code Generation for WCDMA on the StarCore™ SC140/SC1400 Cores, Rev. 1
Example 4. Complex Scrambling of an I-Q/code Multiplexed Signal
;*******************************************************************************
;*
;*
;*
;* received I-Q/code multiplexed signal for WCDMA
;*
;*
;*
;*
;*
;*
;*
;*
;*
;*
;*
;*******************************************************************************
;*
;*
;*
;*
;*******************************************************************************
;--------------------------cmplx_scrambling_param.asm---------------------------
;*******************************************************************************
;
;NUM_ITEREQU19199
;INV_SQRT2 EQU #0.70710678;//1/sqrt(2)
;
;*******************************************************************************
;---------------------------WCDMA COMPLEX SCRAMBLING----------------------------
;*******************************************************************************
main_cmplx_scrambling type func
File:
Function:
Author:
Version/Date:
Target Processor: Star*Core 140
Description:
Module Details:
Registers Used:
d0,d1,d2,d3,d4,d5,d6,d7,d8,d9,d10,d11,d15
r0,r2,r4
entry : jsr
Revision History:
section .data local
endsec
section .text local
[
push d6
push d7
]
[
push r6
push r7
]
include ’cmplx_scrambling_param.asm’
global main_cmplx_scrambling
cmplx_scrambling.asm
formation of complex scrambling code and scrambling of
Imran Ahmed
1.0 Oct 10 2001
Date
----
;//(38400-2)/2
Change Details
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Initials
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