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TMS 420 R3051, R3052 & R3081 Microprocessor Support Instruction Manual
4–1
Maintenance
This chapter contains a circuit description of the probe adapter.
Probe Adapter Circuit Description
The 16R4 is used to latch three rising edge signals for
disassembly
and to buffer
these signals to reduce loading on the CPU. The 16L8 is used to OR the interrupt
lines for the module. The 74FR244 minimizes the load on the user clock and
buffers other signals to keep the clock/signal timing relation the same.
J1771 and J1671 are used to turn off the cache. The SUT drives these lines,
therefore the SUT driver must be disabled to use this option.
Replacing Signal Leads
Information on basic operations describes how to replace signal leads (individual
channel and clock probes).
Replacing Protective Sockets
Information on basic operations describes how to replace protective sockets.