SH7760 Datasheet, PDF (751/1345 Pages) Renesas Technology Corp – SuperHTM RISC engine

In the case of the SSI module configured as a transmitter then each word that is written to SSITDR
is transmitted in order on the serial audio bus.
In the case of the SSI module configured as a receiver each word received on the Serial Audio Bus
is presented for reading in order by SSIRDR.
Figures 20.6 to 20.8 show how 4, 6 and 8 channels are transferred on the serial audio bus.
Note that there are no padding bits in the first example, serial data is transmitted/received first and
followed by padding bits in the second example, and padding bits are transmitted/received first
and followed by serial data in the third example. This selection is purely arbitrary.
SCKP = 0, SWSP = 0, DEL = 0, CHNL = 01, SPDP = don't care, SDTA = don't care
System word length = data word length × 2
SSI_SCK
SSI_WS
SSI_SDATA
LSB MSB
LSB MSB
LSB MSB
LSB MSB
LSB MSB
LSB MSB
LSB MSB
LSB MSB
LSB MSB
Data
word 1
Data
word 2
Data
word 3
Data
word 4
Data
word 1
Data
word 2
Data
word 3
Data
word 4
System word 1
System word 2
System word 1
System word 2
Figure 20.6 Multichannel Format (4 Channels, No Padding)
SCKP = 0, SWSP = 0, DEL = 0, CHNL = 10, SPDP = 1, SDTA = 0
System word length = data word length × 3
SSI_SCK
SSI_WS
SSI_SDATA
MSB
LSB MSB
LSB MSB
LSB
MSB
LSB MSB
LSB MSB
LSB
MSB
Data
word 1
Data
word 2
Data
word 3
Data
word 4
Data
word 5
Data
word 6
System word 1
System word 2
Figure 20.7 Multichannel Format (6 Channels with High Padding)
Rev. 1.0, 02/03, page 701 of 1294