7-14
DSP56309UM/D MOTOROLA
Enhanced Synchronous Serial Interface (ESSI)
ESSI Programming Model
7.4.1.7
CRA Word-length Control (WL[2:0]) Bits 21Ð19
The WL[2:0] bits are used to select the length of the data words being transferred via the
ESSI. Word lengths of 8-, 12-, 16-, 24-, or 32- bits can be selected, as in
ESSI data path programming model in
page 7-32 has additional information about selecting different length data words. The
ESSI data registers are 24 bits long. The ESSI transmits 32-bit words either by duplicating
the last bit eight times when WL[2:0] = 100, or by duplicating the first bit eight times
when WL[2:0] = 101. The WL[2:0] bits are cleared by a hardware RESET signal or by a
software RESET instruction.
7.4.1.8
CRA Select SC1 (SSC1) Bit 22
The SSC1 bit controls the functionality of the SC1 signal. This bit is only valid when the
ESSI is configured in synchronous mode (i.e., if the CRB synchronous/asynchronous bit
(SYN) is set), and transmitter 2 is disabled (i.e., if transmit enable (TE2) = 0). If SSC1 is set
and SC1 is configured as an output (SCD1 = 1), then the SC1 signal acts as the driver
enabled signal of transmitter 0. This enables an external buffer for the transmitter 0
output.
If SSC1 is cleared, SC1 acts as the serial I/O flag.
7.4.1.9
CRA Reserved Bit 23
This bit is reserved. It is read as 0 and should be written with 0.
Table 7-2
ESSI Word Length Selection
WL2
WL1
WL0
Number of Bits/Word
0
0
0
8
0
0
1
12
0
1
0
16
0
1
1
24
1
0
0
32
(valid data in the first 24 bits)
1
0
1
32
(valid data in the last 24 bits)
1
1
0
Reserved
1
1
1
Reserved
Summary of Contents for DSP56309
Page 25: ...xxii DSP56309UM D MOTOROLA Figure D 25 Port E Registers PCRE PRRE PDRE D 39 ...
Page 30: ...MOTOROLA DSP56309UM D 1 1 SECTION 1 DSP56309 OVERVIEW ...
Page 47: ...1 18 DSP56309UM D MOTOROLA DSP56309 Overview DSP56309 Architecture Overview ...
Page 48: ...MOTOROLA DSP56309UM D 2 1 SECTION 2 SIGNAL CONNECTION DESCRIPTIONS ...
Page 85: ...2 38 DSP56309UM D MOTOROLA Signal Connection Descriptions OnCE JTAG Interface ...
Page 86: ...MOTOROLA DSP56309UM D 3 1 SECTION 3 MEMORY CONFIGURATION ...
Page 104: ...MOTOROLA DSP56309UM D 4 1 SECTION 4 CORE CONFIGURATION ...
Page 124: ...MOTOROLA DSP56309UM D 5 1 SECTION 5 GENERAL PURPOSE I O ...
Page 125: ...5 2 DSP56309UM D MOTOROLA General Purpose I O 5 1 INTRODUCTION 5 3 5 2 PROGRAMMING MODEL 5 3 ...
Page 128: ...MOTOROLA DSP56309UM D 6 1 SECTION 6 HOST INTERFACE HI08 ...
Page 166: ...MOTOROLA DSP56309UM D 7 1 SECTION 7 ENHANCED SYNCHRONOUS SERIAL INTERFACE ESSI ...
Page 212: ...MOTOROLA DSP56309UM D 8 1 SECTION 8 SERIAL COMMUNICATION INTERFACE SCI ...
Page 241: ...8 30 DSP56309UM D MOTOROLA Serial Communication Interface SCI GPIO Signals and Registers ...
Page 242: ...MOTOROLA DSP56309UM D 9 1 SECTION 9 TRIPLE TIMER MODULE ...
Page 269: ...9 28 DSP56309UM D MOTOROLA Triple Timer Module Timer Operational Modes ...
Page 270: ...MOTOROLA DSP56309UM D 10 1 SECTION 10 ON CHIP EMULATION MODULE ...
Page 302: ...MOTOROLA DSP56309UM D 11 1 SECTION 11 JTAG PORT ...
Page 369: ...C 22 DSP56309UM D MOTOROLA DSP56309 BSDL Listing ...
Page 370: ...MOTOROLA DSP56309UM D D 1 APPENDIX D PROGRAMMING REFERENCE ...
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