Data Sheet
June 2001
DSP16410B Digital Signal Processor
170
Agere Systems—Proprietary
Use pursuant to Company instructions
Agere Systems Inc.
4 Hardware Architecture
(continued)
4.16 Serial Interface Unit (SIU)
(continued)
4.16.12 Channel Mode—32 Channels or Less in
Two Subframes or Less
(continued)
If using channel mode, the user performs the following
steps in software:
1. Configure the number of channels in the frame
structure (1 to 128) by programming the IFLIM[6:0]
field (
SCON1
[6:0]—see
Table 102 on page 183
) with
the frame size for input and the OFLIM[6:0] field
(
SCON2
[6:0]—see
Table 103 on page 184
) with the
frame size for output.
2. Configure the channel size (4, 8, 12, or 16 bits) by
writing the ISIZE[1:0] and OSIZE[1:0] fields
(
SCON0
[4:3] and
SCON0
[12:11]—see
Table 101 on
page 182
). Select LSB-first or MSB-first by pro-
gramming the IMSB and OMSB fields (
SCON0
[2]
and
SCON0
[10]). Configure the data format by pro-
gramming the IFORMAT[1:0] and OFORMAT[1:0]
fields (
SCON0
[1:0] and
SCON0
[9:8]).
3. Disable frame mode by clearing the IFRAME field
(
SCON1
[7]—see
Table 102 on page 183
) and the
OFRAME field (
SCON2
[7]—see
Table 103 on
page 184
).
4. Select the number of subframes (one or two) to be
enabled. If two subframes are enabled, one must be
even and one must be odd. See step 5.
5. Select the active subframe(s) and channels within
each subframe. Tables
93
to
97
further detail the bit
fields described below.
— To activate an even input subframe, set the
ISFIDV_E field (
SCON3
[2]—see
Table 104 on
page 185
). Also program the ISFID_E[1:0] field
(
SCON3
[1:0]) with the address of the active even
subframe (active subframe number is
2
×
ISFID_E). Within the active subframe, up to
16 logical channels can be individually enabled
via the ISFVEC_E[15:0] field (
SCON4
—see
Table 105 on page 186
). For each enabled chan-
nel, assign one of two DMAU SWT channels by
setting or clearing the corresponding bit in
ICIX0
(
Table 120 on page 196
).
— To activate an odd input subframe, set the
ISFIDV_O field (
SCON3
[5]—see
Table 104 on
page 185
). Also program the ISFID_O[1:0] field
(
SCON3
[4:3]) with the address of the active odd
subframe (active subframe number is
(2
×
ISFID_O) + 1). Within the active subframe,
up to 16 logical channels can be individually
enabled via the ISFVEC_O[15:0] field
(
SCON5
—see
Table 106 on page 186
). For each
enabled channel, assign one of two DMAU SWT
channels by setting or clearing the corresponding
bit in
ICIX1
(
Table 120 on page 196
).
— To activate an even output subframe, set the
OSFIDV_E field (
SCON3
[10]). Also program the
OSFID_E[1:0] field (
SCON3
[9:8]) with the
address of the active even subframe (active sub-
frame number is 2
×
OSFID_E). Within the
active subframe, up to 16 logical channels can be
individually enabled via the OSFVEC_E[15:0]
field (
SCON6
—see
Table 107 on page 187
). Any
enabled channel can be individually masked via
the OSFMSK_E[15:0] field (
SCON8
—see
Table 109 on page 187
). Masking an output
channel retains the data structure (the DMAU
counters are updated) but does not drive data
onto SOD for that channel period. For each
enabled channel, assign one of two DMAU SWT
channels by setting or clearing the corresponding
bit in
OCIX0
(
Table 119 on page 195
).
— To activate an odd output subframe, set the
OSFIDV_O field (
SCON3
[13]). Also program the
OSFID_O[1:0] field (
SCON3
[12:11]) with the
address of the active odd subframe (active sub-
frame number is (2
×
OSFID_O) + 1). Within the
active subframe, up to 16 logical channels can be
individually enabled via the OSFVEC_O[15:0]
field (
SCON7
—see
Table 108 on page 187
). Any
enabled channel can be individually masked via
the OSFMSK_O[15:0] field (
SCON9
—see
Table 110 on page 187
). Masking an output
channel retains the data structure (the DMAU
counters are updated) but does not drive data
onto SOD for that channel period. For each
enabled channel, assign one of two DMAU SWT
channels by setting or clearing the corresponding
bit in
OCIX1
(
Table 119 on page 195
).
6. Select passive vs. active bit clocks and frame syncs
(see
Table 4.16.5 on page 158
for details).
7. Program the IINTSEL[1:0] field (
SCON10
[12:11])
OINTSEL[1:0] field (
SCON10
[14:13]) as required by
the application.
8. Begin processing the active channels by clearing the
IRESET field (
SCON1
[10]—see
Table 102 on
page 183
) and the ORESET field (
SCON2
[10]—see
Table 103 on page 184
). Further user software
intervention for SIU configuration is only required to
redefine the subframe enable, the subframe ID, or
the active channels within a subframe and their
associated channel index values.