GC5316_14 Datasheet, PDF (55/76 Pages) Texas Instruments – HIGH-DENSITY DIGITAL DOWNCONVERTER AND UPCONVERTER

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duc_counter_width
D 1C00
1C
ssel_comp_pmeter_0
ssel_comp_pmeter_1
ssel_comp_pmeter_2
ssel_comp_pmeter_3
ssel_txsync_out
U 1C00
1D
U 1C00
1D
U 1C00
1D
U 1C00
1D
U 1C00
1E
0
8
12
3
8
3
4
3
0
3
0
3
GC5316
SLWS154A − JANUARY 2004 − REVISED MARCH 2004
0
Sets the width of the counter generated
sync pulse in TX clock cycles, from 1 to
256. The width of this pulse must be long
enough to be captured by the slowest
block to use the DUC counter sync.
0
Selects the sync source for composite
power meter 0.
0
Selects the sync source for composite
power meter 1.
0
Selects the sync source for composite
power meter 2.
0
Selects the sync source for composite
power meter 3.
0
Selects the sync source for the
TXSYNC_OUT pin.
5.1.7 DDC or DUC Channel Controls
These controls are used by both the DDC or DUC channels. These follow either the ddc <channel_number> or the
duc <channel_number> keywords in the cmd5316 configuration file.
VARIABLE NAME
cdma_mode
crastarttap_pfir
crastarttap_cfir
pfir_gain
cfir_gain
cic_scale_a
cic_scale_b
cic_interp_decim
TYPE
PAGE
ADDRESS
LSB
POSITION
BIT
WIDTH
DEFAULT
U 0100
0
15
1
1
C 0100
0
8
5
0
C 0100
0
3
5
0
U 0100
1
13
3
0
U 0100
1
U 0100
0E
5
1
0
11
5
0
U 0100
0E
U 0100
0E
6
5
0
0
5
24
DESCRIPTION
When asserted the block is in the dual channel
CDMA2000 mode.
These bits define the number of taps that PFIR
uses for the filtering. Another way of looking at
these bits is that this value is the location in the
RAM of the center tap. DUC PFIR: (2 x
crastarttap_pfir) +1, DDC PFIR:
4(crastarttap_pfir+1), DDC PFIR long mode:
8(crastarttap_pfir+1). Note: crastarttap_pfir must
be odd for a DUC
These bits define the number of taps that CFIR
uses for the filtering. DUC CFIR: (2 x
crastarttap_cfir) +1, DDC CFIR:
2(crastarttap_cfir+1). Note: crastarttap_cfir must
be odd for a DUC
This is the gain for the PFIR. The range is from
2e−19 to 2e−12 for the receive PFIR. (“000” =
2e−19 and “111” = 2e−12) For the transmit PFIR
however, only the LSB of the word is used and it
selects either 2e−18 when ‘0’ or 2e−17 when ‘1’.
This is the gain for the CFIR. 0= 2e−19, 1=
2e−18.
This sets the gain shift at the output of the CDMA
A channel (or UMTS channel) CIC. 0x00 is no
shift, each increment by 1 increases the signal
amplitude by 2X.
This sets the gain shift at the output of the CDMA
B channel CIC. 0x00 is no shift, each increment
by 1 increases the signal amplitude by 2X.
Sets the CIC interpolation, where interpolation is
cic_interp_decim + 1 in the digital up converters.
Sets the CIC decimation, where decimation is
cic_interp_decim + 1 in the digital down
converters.
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