Enhanced Synchronous Serial Interface (ESSI)
Operating Modes
MOTOROLA
DSP56309UM/D 7-39
1. Configure interrupt service routine (ISR)
a. Load vector base address register.
VBA (b23:8)
b. Define I_VEC to be equal to the VBA value (if that is nonzero). If it is defined,
I_VEC must be defined for the assembler before the interrupt equate file is
included.
c. Load the exception vector table entry: two-word fast interrupt or
jump/branch to subroutine (long interrupt).
p:I_SI0TD
2. Configure interrupt trigger/preload transmit data
a. Enable and prioritize overall peripheral interrupt functionality.
IPRP (S0L1:0)
b. Enable peripheral and associated signals.
PCRC (PC5:0)
c. Write data to all enabled transmit registers.
TX00
d. Enable peripheral interrupt-generating function.
CRB (TE0)
e. Enable specific peripheral interrupt.
CRB0 (TIE)
f. Unmask interrupts at global level.
SR (I1:0)
Notes:
1.
The example material to the right of the steps above shows register settings
for configuring an ESSI0 transmit interrupt using transmitter 0.
2.
The order of the steps is optional except that the interrupt trigger
configuration must not be completed until the ISR configuration has been
completed. Since 2d can cause an immediate transmit without generating
an interrupt, perform the transmit data preload in 2c before 2d to insure
valid data is sent in the first transmission.
3.
After the first transmit, subsequent transmit values are typically loaded
into TXnn by the ISR (one value per register per interrupt). Therefore, if N
items are to be sent from a particular TXnn, the ISR will need to load the
transmit register (N Ð 1) times.
4.
Steps d and e can be performed using a single instruction.
5.
If an interrupt trigger event occurs at a time when not all interrupt trigger
configuration steps have been performed, the event is ignored forever (the
event is not queued in this case).
6.
If interrupts derived from the core or other peripherals need to be enabled
at the same time as ESSI interrupts, step f should be done last.
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 ...
Page 405: ......
Page 409: ......