8-18
DSP56309UM/D MOTOROLA
Serial Communication Interface (SCI)
SCI Programming Model
8.3.3.5
SCCR Transmit Clock Source Bit (TCM) Bit 15
TCM selects whether an internal or external clock is used for the transmitter. If TCM is
cleared, the internal clock is used. If TCM is set, the external clock (from the SCLK
signal) is used. Either a hardware RESET signal or a software RESET instruction clears
TCM.
8.3.4
SCI Data Registers
The SCI data registers are divided into two groups: receive and transmit (as in
). There are two receive registersÑa receive data register (SRX) and a
serial-to-parallel receive shift register. There are also two transmit registersÑa transmit
data register (called either STX or STXA) and a parallel-to-serial transmit shift register.
Figure 8-6
SCI Baud Rate Generator
F
core
Divide
By 2
12-bit Counter
Prescaler:
Divide by
1 or 8
CD11ÐCD0
SCP
Internal Clock
Timer
Interrupt
(STMINT)
SCI Core Logic
Uses Divide by 16 for
Asynchronous
Uses Divide by 2 for
Synchronous
COD
SCKP
If Asynchronous
Divide by 1 or 16
If Synchronous
Divide By 2
TO SCLK
F
core
BPS =
64
´
((7
´
SCP + 1)
´
CD + 1)
where:
SCP = 0 or 1
CD = $000 to $FFF
AA0693
Divide
By 2
Divide
By 16
SCKP = 0
SCKP = 1
+
Ð
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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