Figure 7-19 Essi Data Path Programming Model (Shfd = 0) - Motorola DSP56305 User Manual

23
Receive High Byte
7
23
Serial
Receive
Receive High Byte
Shift
Register
7
MSB
8-bit Data
MSB
MSB
MSB
(a) Receive Registers
23
Transmit High Byte
7
23
Transmit High Byte
STD
7
MSB
8-bit Data
MSB
MSB
MSB
(b) Transmit Registers

Figure 7-19 ESSI Data Path Programming Model (SHFD = 0)

MOTOROLA
16 15
Receive Middle Byte
0 7
16 15
Receive Middle Byte
0 7
LSB
0
LSB
12-bit Data
16-bit Data
24-bit Data
16 15
Transmit Middle Byte
0 7
16 15
Transmit Middle Byte
0 7
LSB
0
LSB
12-bit Data
16-bit Data
24-bit Data
DSP56305 User's Manual
Enhanced Synchronous Serial Interface (ESSI)
8 7
Receive Low Byte
0 7
8 7
Receive Low Byte
0 7
16 Bit
12 Bit
8 Bit
WL1, WL0
0 0
LSB
NOTES:
•Data is received MSB first if SHFD = 0
•24-bit fractional format (ALC = 0)
•32-bit mode is not shown
8 7
Transmit Low Byte
0 7
8 7
Transmit Low Byte
0 7
0 0
LSB
NOTES:
•Data is transmitted MSB first ifSHFD = 0
•24-bit fractional format (ALC = 0)
•32-bit mode is not shown
ESSI Programming Model
0
ESSI Receive Data Register
(Read Only)
0
0
0
24 Bit
SRD
Least Significant
Zero Fill
LSB
0
ESSI Transmit Data
Register
(Write Only)
0
0
ESSI Transmit
Shift Register
0
Least Significant
Zero Fill
LSB
AA0686
7-37