Figure 7-17 Essi Data Path Programming Model (Shfd = 1) - Motorola DSP56309 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
MSB
MSB
(a) Receive Registers
23
Transmit High Byte
7
23
Transmit High Byte
7
MSB
8-bit Data
MSB
MSB
MSB
(b) Transmit Registers

Figure 7-17 ESSI Data Path Programming Model (SHFD = 1)

7-32
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
DSP56309UM/D
8 7
Receive Low Byte
0 7
0 7
Receive Low Byte
0 7
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
0 7
Transmit Low Byte
0 7
16 Bit
12 Bit
8 Bit
0 0
LSB
NOTES:
Data is received MSB first if SHFD = 0.
4-bit fractional format (ALC = 0).
32-bit mode is not shown.
0
ESSI Receive Data Register
(Read Only)
0
0
ESSI Receive
Shift Register
0
Least Significant
Zero Fill
LSB
0
ESSI Transmit Data
Register
(Write Only)
0
0
ESSI Transmit Shift
Register
0
24 Bit
WL1, WL0
Least Significant
Zero Fill
LSB
MOTOROLA
STD
AA0687