User manual

MPLAB
®
REAL ICE
™
In-Circuit Emulator User’s Guide
DS51616B-page 84 © 2008 Microchip Technology Inc.
• Does the MPLAB REAL ICE in-circuit emulator have complex breakpoints?
Yes. You can break based on a value in a data memory location. You can also do
sequenced breakpoints, where several events are happening before it breaks, but
you can only do 2 sequences instead of 4, as you can in the MPLAB ICE 2000.
You can also do an AND condition and PASS counts. See
Section 11.3.1 “Breakpoints Dialog” for more information.
• One of the probe pins is labeled 5V. How much drive capability does this probe
have?
This is a monitoring function (allows you to see what V
DD is actually being applied
and used on the driver buffers). The MPLAB REAL ICE in-circuit emulator cannot
provide power to the target.
• Are any of the driver boards optoisolated or electrically isolated?
They are DC optoisolated, but not AC optoisolated. To apply high voltage (120V)
to the current system, see the optional opto-isolation board (AC244005).
• What limitations are there with the 5 or 6 pins only?
The limitations are with the cable used. The standard ICSP RJ-11 cable does not
allows for clock speeds greater than about 15 Mb/sec. dsPIC33F DSCs running at
full speed are greater than the 15 Mb/sec limit. For these high-speed applications,
the Performance Pak (high-speed) cable interface is required.
• Will this slow down the running of the program?
There is no cycle stealing with the MPLAB REAL ICE in-circuit emulator. The
output of data is performed by the state machine in the silicon.
• How do I connect CLK and DAT when using high-speed communications?
These connections are optional and used for SPI trace. For more information, see
Section 2.5.2 “SPI Trace Connections (High-Speed Communication Only)”.
• What is meant by the data rate is limited to 15 MIPS, when using the standard
board? Is this caused by the core processor or transfer rate?
The standard board uses the RJ-11 cable and has a limitation on how fast data
can reliably be transmitted when using trace. The top end is when the processor
has an operational speed of 15 MIPS. The trace clock is derived from the main
system clock of the device.
• To debug a dsPIC
®
DSC running at 30 MIPS, is the high-speed board necessary
to do even basic debugging?
Basic debugging at any device frequency can be accomplished with either
standard or high-speed (Performance Pak) communications.
• If the high speed board is necessary for a dsPIC DSC to run at 30 MIPS, can this
be done using the high speed to standard converter board on the target side?
It is recommended that at high device operational frequencies, the slower cable
not be used. This introduces signal integrity issues, due to the lower quality of
cable transmission, when using the RJ-11 converter board.
• If the high-speed receiver board is used, do pins 7-8 have to be connected, or can
they just be left open?
They can be left open. The high-speed receiver board weakly pulls them down.
• What is the function of pin 6, the auxiliary pin?
There is no function on pin 6. It is a legacy connection, compatible with the typical
ICSP 6-pin header definition.