
This information applies to a product under development. Its characteristics and specifications are subject to change without notice. Analog
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15
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ADSP-21992
August 2002
PRELIMINARY TECHNICAL DATA
 Trace instruction execution
 Profile program execution
 Fill and dump memory
 Source level debugging
 Create custom debugger windows
The VisualDSP IDE 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 syntax high-
lighting in the VisualDSP editor. This capability permits:
 Control how the development tools process inputs and 
generate outputs.
 Maintain a one-to-one correspondence with the tool’s 
command line switches.
Analog Devices DSP emulators use the IEEE 1149.1 JTAG 
test access port of the ADSP-21992 processor to monitor 
and control the target board processor during emulation. 
The emulator provides full-speed emulation, allowing 
inspection and modification of memory, registers, and 
processor stacks. Nonintrusive in-circuit emulation is 
assured by the use of the processor’s JTAG interface—the 
emulator does not affect target system loading or timing.
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 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 (Target)
The White Mountain DSP (Product Line of Analog 
Devices, Inc.) family of emulators are tools that every DSP 
developer needs to test and debug their hardware and 
software system.  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 internals of the 
DSP, allowing the developer to load code, set breakpoints, 
observe variables, observe memory, examine registers, etc.  
The DSP must be halted to send data and commands, but 
once an operation is 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’s design must include the 
interface between an Analog Devices JTAG DSP and the 
emulation header on a custom DSP target board. The 
following sections provide the guidelines for design that help 
eliminate possible JTAG emulation port problems.
Target Board Connector
The emulator interface to an ADI JTAG DSP is a 14-pin 
header, as shown in 
Figure 6
.  The customer must supply 
this header on their target board in order to communicate 
with the emulator.  The interface consists of a standard dual 
row 0.025" square post header, set on 0.1" x 0.1" spacing, 
with a minimum post length of 0.235".  Pin 3 is the key 
position used to prevent the pod from being inserted back-
wards.  This pin must be clipped on the target board.
Also, the clearance (length, width, and height) around the 
header must be considered.  Leave a clearance of at least 
0.15” and 0.10” around the length and width of the header, 
and reserve a height clearance to attach and detach the pod 
connector.  For more information, see 
Layout Require-
ments on page 17
.
As can be seen in 
Figure 6
, there are two sets of signals on 
the header.  There are the standard JTAG signals TMS, 
TCK, TDI, TDO, TRST and , EMU used for emulation 
purposes (via an emulator).  There are also secondary JTAG 
signals BTMS, BTCK, BTDI, and BTRST that are option-
ally used for board-level (boundary scan) testing.  The "B" 
signals would be connected to a separate on-board JTAG 
boundary scan controller if used.  Most customers will never 
use the "B" signals.  If they will not be used, tie all of them 
to ground as shown in figure 2.
Note: BTCK can alternately be pulled up (for some older 
silicon) to VDD (+5V, +3.3V, or +2.5V) using a 4.7K  
resistor, as described in previous documents.  Tying the 
signal to ground is universal and will work for all silicon.
When the emulator is not connected to this header, place 
jumpers across BTMS, BTCK, BTRST, and BTDI as 
shown in 
Figure 7
.  This holds the JTAG signals in the 
correct state to allow the DSP to run free.  Remove all the 
jumpers when connecting the emulator to the JTAG header.
Figure 6. JTAG Target Board Connector for JTAG 
Equiped Analog Devices DSP (Jumpers in 
Place)
TOP VIEW
13
14
11
12
9
10
9
7
8
5
6
3
4
1
2
EMU
GND
TMS
TCK
TRST
TDI
TDO
GND
KEY (NO PIN)
BTMS
BTCK
BTRST
BTDI
GND