Tcr Transmit Network Mode Control (Tmod1-Tmod0) - Bits 9-8 - Freescale Semiconductor DSP56374 User Manual

ESAI Programming Model
8.3.2.9

TCR Transmit Network Mode Control (TMOD1-TMOD0) - Bits 9-8

The TMOD1 and TMOD0 bits are used to define the network mode of ESAI transmitters according to
frame rate divider determines the word transfer rate – one word is transferred per frame sync during the frame sync time slot, as shown in
Figure 8-6. In network mode, it is possible to transfer a word for every time slot, as shown in
Operating Modes.
In order to comply with AC-97 specifications, TSWS4-TSWS0 should be set to 00011 (20-bit slot, 20-bit word length), TFSL and TFSR
should be cleared, and TDC4-TDC0 should be set to $0C (13 words in frame). If TMOD[1:0]=$11 and the above recommendations are
followed, the first slot and word will be 16 bits long, and the next 12 slots and words will be 20 bits long, as required by the AC97 protocol.
TMOD1
0
0
0
1
1
8-12
Table 8-4. Transmit Network Mode Selection
TMOD0 TDC4-TDC0
0 $0-$1F
1 $0
1 $1-$1F
0 X
1 $0C
DSP56374 Users Guide, Rev. 1.2
Figure
Figure 8-6. For more details, see
Transmitter Network Mode
Normal Mode
On-Demand Mode
Network Mode
Reserved
AC97
8-4. In the normal mode, the
Section 8.4,
Freescale Semiconductor