Figure 7-20 Essi Data Path Programming Model (Shfd = 1) - Motorola DSP56305 User Manual

Enhanced Synchronous Serial Interface (ESSI)
ESSI Programming Model
23
Receive High Byte
7
23
Receive High Byte
SRD
7
MSB
8-bit Data
MSB
12-bit Data
MSB
MSB
(a) Receive Registers
23
Transmit High Byte
7
23
Transmit High Byte
7
MSB
8-bit Data
MSB
12-bit Data
MSB
MSB
(b) Transmit Registers

Figure 7-20 ESSI Data Path Programming Model (SHFD = 1)

7-38
16 15
Receive Middle Byte
0 7
16 15
Receive Middle Byte
0 7
LSB
0 0
LSB
LSB
16-bit Data
24-bit Data
16 15
Transmit Middle Byte
0 7
16 15
Transmit Middle Byte
0 7
LSB
0 0
LSB
LSB
16-bit Data
24-bit Data
DSP56305 User's Manual
8 7 0
Receive Low Byte
0 7 0
8 7 0
Receive Low Byte
0 7
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 0
Transmit Low Byte
0 7 0
8 7 0
Transmit Low Byte
0 7 0
16 Bit
12 Bit
8 Bit
0
LSB
NOTES:
•Data is received MSB first if SHFD = 0
•24-bit fractional format (ALC = 0)
•32-bit mode is not shown
ESSI Receive Data Register
(Read Only)
ESSI Receive
Shift Register
0
Least Significant
Zero Fill
ESSI Transmit Data
Register
(Write Only)
ESSI Transmit Shift
Register
24 Bit
STD
WL1, WL0
Least Significant
Zero Fill
AA0687
MOTOROLA