7-12
DSP56309UM/D MOTOROLA
Enhanced Synchronous Serial Interface (ESSI)
ESSI Programming Model
Note:
The combination PSR = 1 and PM[7:0] = $00 (dividing F
core
by 2) can cause
synchronization problems and should not be used.
7.4.1.4
CRA Frame Rate Divider Control DC[4:0] Bits 16Ð12
The values of the DC[4:0] bits control the divide ratio for the programmable frame rate
dividers used
to generate the frame clocks. In network mode, this ratio can be
interpreted as the number of words per frame minus one. In normal mode, this ratio
determines the word transfer rate.
The divide ratio can range from 1 to 32 (DC = 00000 to 11111) for normal mode and 2 to
32 (DC = 00001 to 11111) for network mode. A divide ratio of one (DC = 00000) in
network mode is a special case known as on-demand mode. In normal mode, a divide
ratio of one (DC = 00000) provides continuous periodic data word transfers. A bit-length
frame sync must be used in this case and is selected by setting the FSL[1:0] bits in the
CRA to (01). Both the hardware RESET signal and the software RESET instruction clear
DC[4:0].
The ESSI frame sync generator functional diagram is shown in
Figure 7-9
ESSI Clock Generator Functional Block Diagram
SCn0
SCKn
CRB(SCD0)
CRB(SCKD)
CRB(SYN) = 1
SCD0 = 0
RCLOCK
TCLOCK
Internal Bit Clock
SYN = 1
CRA(WL2:0)
RX Shift Register
TX Shift Register
/1 or /8
/1 to /256
F
CORE
RX
Word
Clock
SYN = 0
SCD0 = 1
Note: 1. F
CORE
is the DSP56300 Core internal
clock frequency.
2. ESSI internal clock range:
min = F
OSC
/4096
max = F
OSC
/4
3. ÔnÕ in signal name is ESSI # (0 or 1)
AA0679
Sync:
TX #1, or
Async:
RX clk
Sync:
TX/RX clk
Async:
TX clk
0
0
0
255
CRA(PSR)
CRA(PM7:0)
/8, /12, /16, /24, /32
1
2
3
4,5
Flag0 Out
(Sync Mode)
CRB(OF0)
CRB(TE1)
TX #1
Flag0 In
(Sync Mode)
SSISR(IF0)
1
SYN = 0
0
/8, /12, /16, /24, /32
1
2
3
4,5
/2
CRA(WL2:0)
TX
Word
Clock
Flag0
(Opposite
from SSI)
or
Содержание DSP56309
Страница 25: ...xxii DSP56309UM D MOTOROLA Figure D 25 Port E Registers PCRE PRRE PDRE D 39 ...
Страница 30: ...MOTOROLA DSP56309UM D 1 1 SECTION 1 DSP56309 OVERVIEW ...
Страница 47: ...1 18 DSP56309UM D MOTOROLA DSP56309 Overview DSP56309 Architecture Overview ...
Страница 48: ...MOTOROLA DSP56309UM D 2 1 SECTION 2 SIGNAL CONNECTION DESCRIPTIONS ...
Страница 85: ...2 38 DSP56309UM D MOTOROLA Signal Connection Descriptions OnCE JTAG Interface ...
Страница 86: ...MOTOROLA DSP56309UM D 3 1 SECTION 3 MEMORY CONFIGURATION ...
Страница 104: ...MOTOROLA DSP56309UM D 4 1 SECTION 4 CORE CONFIGURATION ...
Страница 124: ...MOTOROLA DSP56309UM D 5 1 SECTION 5 GENERAL PURPOSE I O ...
Страница 125: ...5 2 DSP56309UM D MOTOROLA General Purpose I O 5 1 INTRODUCTION 5 3 5 2 PROGRAMMING MODEL 5 3 ...
Страница 128: ...MOTOROLA DSP56309UM D 6 1 SECTION 6 HOST INTERFACE HI08 ...
Страница 166: ...MOTOROLA DSP56309UM D 7 1 SECTION 7 ENHANCED SYNCHRONOUS SERIAL INTERFACE ESSI ...
Страница 212: ...MOTOROLA DSP56309UM D 8 1 SECTION 8 SERIAL COMMUNICATION INTERFACE SCI ...
Страница 241: ...8 30 DSP56309UM D MOTOROLA Serial Communication Interface SCI GPIO Signals and Registers ...
Страница 242: ...MOTOROLA DSP56309UM D 9 1 SECTION 9 TRIPLE TIMER MODULE ...
Страница 269: ...9 28 DSP56309UM D MOTOROLA Triple Timer Module Timer Operational Modes ...
Страница 270: ...MOTOROLA DSP56309UM D 10 1 SECTION 10 ON CHIP EMULATION MODULE ...
Страница 302: ...MOTOROLA DSP56309UM D 11 1 SECTION 11 JTAG PORT ...
Страница 369: ...C 22 DSP56309UM D MOTOROLA DSP56309 BSDL Listing ...
Страница 370: ...MOTOROLA DSP56309UM D D 1 APPENDIX D PROGRAMMING REFERENCE ...
Страница 405: ......
Страница 409: ......