Renesas SH7781 User Manual

Page 1335

26. Serial Sound Interface (SSI) Module

Rev.1.00 Jan. 10, 2008 Page 1305 of 1658

REJ09B0261-0100

Bit Bit

Name

Initial
Value R/W Description

PDTA

R/W

Parallel Data Alignment

This bit is ignored if CPEN = 1.

If the data word length = 32, 16 or 8 then this bit has no
meaning.

This bit is applied to SSIRDR in receive mode and to
SSITDR in transmit mode.

0: Parallel data (SSITDR or SSIRDR) is left aligned
1: Parallel data (SSITDR or SSIRDR) is right aligned

• DWL = 000 (data word length: 8 bits), PDTA ignored

All data bits in SSIRDR or SSITDR are used on the
audio serial bus. Four data words are
transmitted/received in each 32-bit access. The first
data word is derived from bits 7 to 0, the second
from bits 15 to 8, the third from bits 23 to 16 and the
last data word is stored in bits 31 to 24.

• DWL = 001 (data word length: 16 bits), PDTA

ignored
All data bits in SSIRDR or SSITDR are used on the
audio serial bus. Two data words are
transmitted/received in each 32-bit access. The first
data word is derived from bits 15 to 0 and the
second data word is stored in bits 31 to 16.

• DWL = 010, 011, 100, 101 (data word length: 18,

20, 22 and 24 bits), PDTA = 0 (left aligned)

• The data bits which are used in SSIRDR or SSITDR

are the following:
Bits 31 to (32 – number of bits having data word
length specified by DWL).
If DWL = 011 then data word length is 20 bits and
bits 31 to 12 are used of either SSIRDR or SSITDR.
All other bits are ignored or reserved.

• DWL = 010, 011, 100, 101 (data word length: 18,

20, 22 and 24 bits), PDTA = 1 (right aligned)
The data bits which are used in SSIRDR or SSITDR
are the following:
Bits (number of bits having data word length
specified by DWL - 1) to 0.
If DWL = 011 then data word length is 20 bits and
bits 19 to 0 are used of either SSIRDR or SSITDR.
All other bits are ignored or reserved.

• DWL = 110 (data word length: 32 bits), PDTA

ignored
All data bits in SSIRDR or SSITDR are used on the
audio serial bus.