adsp-21991 Analog Devices, Inc., adsp-21991 Datasheet - Page 14

• Manufacturer Part Number: adsp-21991
• Description: Mixed Signal Dsp Controller
• Manufacturer: Analog Devices, Inc.

ADSP-21991
Debugging both C/C++ and assembly programs with the
VisualDSP++ debugger, programmers can:
• View mixed C/C++ and assembly code (interleaved
• Insert breakpoints
• Set conditional breakpoints on registers, memory,
• Trace instruction execution
• Perform linear or statistical profiling of program
• Fill, dump, and graphically plot the contents of memory
• Perform source level debugging
• Create custom debugger windows
The VisualDSP++ IDDE lets programmers define and manage
DSP software development. Its dialog boxes and property pages
let programmers configure and manage all of the ADSP-219x
development tools, including the color syntax highlighting in the
VisualDSP++ editor. This capability permits programmers to:
• Control how the development tools process inputs and
• Maintain a one-to-one correspondence with the
The VisualDSP++ Kernel (VDK) incorporates scheduling and
resource management tailored specifically to address the memory
and timing constraints of DSP programming. These capabilities
enable engineers to develop code more effectively, eliminating the
need to start from the very beginning, when developing new
application code. The VDK features include Threads, Critical
and Unscheduled regions, Semaphores, Events, and Device flags.
The VDK also supports Priority-based, Preemptive, Coopera-
tive, and Time-Sliced scheduling approaches. In addition, the
VDK was designed to be scalable. If the application does not use
a specific feature, the support code for that feature is excluded
from the target system.
Because the VDK is a library, a developer can decide whether to
use it or not. The VDK is integrated into the VisualDSP++ devel-
opment environment, but can also be used via standard
command line tools. When the VDK is used, the development
environment assists the developer with many error-prone tasks
and assists in managing system resources, automating the gener-
ation of various VDK based objects, and visualizing the system
state, when debugging an application that uses the VDK.
VCSE is Analog Devices technology for creating, using, and
reusing software components (independent modules of substan-
tial functionality) to quickly and reliably assemble software
applications. Download components from the Web and drop
them into the application. Publish component archives from
within VisualDSP++. VCSE supports component implementa-
tion in C/C++ or assembly language.
Use the Expert Linker to visually manipulate the placement of
code and data on the embedded system. View memory utilization
in a color-coded graphical form, easily move code and data to
different areas of the DSP or external memory with the drag of
the mouse, examine run time stack and heap usage. The Expert
source and object information)
and stacks
execution
generate outputs
command line switches of the tool
–14–
Linker is fully compatible with existing Linker Definition File
(LDF), allowing the developer to move between the graphical
and textual environments.
Analog Devices DSP emulators use the IEEE 1149.1 JTAG Test
Access Port of the ADSP-21991 processor to monitor and control
the target board processor during emulation. The emulator
provides full speed emulation, allowing inspection and modifica-
tion of memory, registers, and processor stacks. Non intrusive
in-circuit emulation is assured by the use of the processor JTAG
interface—target system loading and timing are not affected by
the emulator.
In addition to the software and hardware development tools
available from Analog Devices, third parties provide a wide range
of tools supporting the ADSP-219x processor family. Hardware
tools include ADSP-219x DSP PC plug-in cards. Third party
software tools include DSP libraries, real-time operating systems,
and block diagram design tools.
Designing an Emulator-Compatible DSP Board
The Analog Devices family of emulators are tools that every DSP
developer needs to test and debug hardware and software
systems. Analog Devices has supplied an IEEE 1149.1 JTAG Test
Access Port (TAP) on each JTAG DSP. The emulator uses the
TAP to access the internal features of the DSP, allowing the
developer to load code, set breakpoints, observe variables,
observe memory, and examine registers. The DSP must be halted
to send data and commands, but once an operation has been
completed by the emulator, the DSP system is set running at full
speed with no impact on system timing.
To use these emulators, the target board must include a header
that connects the JTAG port of the DSP to the emulator.
For details on target board design issues including mechanical
layout, single processor connections, multiprocessor scan chains,
signal buffering, signal termination, and emulator pod logic, see
the EE-68: Analog Devices JTAG Emulation Technical Reference on
the Analog Devices website (www.analog.com)—use site search
on “EE-68.” This document is updated regularly to keep pace
with improvements to emulator support.
Additional Information
This data sheet provides a general overview of the ADSP-21991
architecture and functionality. For detailed information on the
ADSP-21991 embedded DSP core architecture, instruction set,
communications ports and embedded control peripherals, refer
to the ADSP-2199x Mixed Signal DSP Controller Hardware
Reference.
PIN FUNCTION DESCRIPTIONS
ADSP-21991 pin definitions are listed in
21991 inputs are asynchronous and can be asserted asynchro-
nously to CLKIN (or to TCK for TRST).
Unused inputs should be tied or pulled to V
for ADDR21–0, DATA15–0, PF7-0, and inputs that have
internal pull-up or pull-down resistors (TRST, BMODE0,
BMODE1, BMODE2, BYPASS, TCK, TMS, TDI, PWMPOL,
PWMSR, and RESET)—these pins can be left floating. These
Table
DDEXT
or GND, except
4. All ADSP-
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