HP 16610A, Руководство пользователя

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Chapter 3: Connecting to a Target System
Designing the Target System for an Emulation Probe/Module
Designing the Target System for an Emulation
Probe/Module
When using the MPC5xx emulation probe/module, you need to be
aware of the requirements it makes of target systems, and you need to
consider how and when the emulation probe/module connects to the
target system.
Target System Requirements
The DSDI and DSCK signals must not be actively driven by the target
system when the debug port is being used.
The RESET and SRESET signals from the debug connector must be
ORed with the respective RESET and SRESET signals that connect to
the processor on the target system. They can be logically ORed or
“wire-ORed” on the board. The emulation probe/module drives RESET
and SRESET through 100 ohm resistors with an open-collector drivers.
There is also 1.79 Kohm pullup to 3.3 volts on the RESET and SRESET
lines.
The HP emulation probe/module adds about 40 pF to all target system
signals routed to the debug connector. This added capacitance may
reduce the rise time of the RESET and SRESET signals beyond the
processor specifications. If so, the target may need to increase the pull-
up current on these signal lines.
Additional target requirements may be specified in the release notes in
the “readme” file on the provided floppy disk.
Debug Port Connection
If you are using the HP E2490A analysis probe for MPC505/509
microprocessors, your target system doesn’t need a debug port
connector and you don’t have to use the supplied target interface
module to connect to it because the analysis probe has a built-in
connector for the emulation probe/module. Otherwise, the emulation