RS_Telecom IP
RM0082
776/844
Doc ID 018672 Rev 1
Figure 95.
Sample management on even frame
In case of buffering mode, on the TDM side, for a given channel, during
frame n
, first the
sample of
frame n
(provided by CPU) is read on the DOUT line and then the input sample of
frame n
from DIN line is stored at the same place.
Figure 96.
Read/write sequence during frame N of a buffer for a given channel
The address generation mechanism allows buffer extension when less than 16 channels are
used.
The address is computed with four parameters
1.
The bank bit
2.
The channel number
(programmed in [19:16] bits of
register
and selected on the basis of number of channels given by [26:24] bits of the same
register)
3.
The frame counter
4.
The offset bits
(programmed in [23:22] of
register and
selected on the basis of number of samples given by [21:20] bits of the same
register)
To/From
TDM
0000
3FFF
4000
7FFF
Odd Buffer
Even Buffer
byte0
byte1
byte2
byte3
1
st
offset bit
2
nd
offset bit
10 bits frame
counter
Channel
Bank bit
To/From
CPU
Type
Frame N
Frame N
Frame N-1
Frame N-1
...
readsample
Of frameN
writesample
Of frameN
sample
of frame n+1
readsample
Of frameN
writesample
Of frameN
sample
of frame n+2