HP 64783A, Руководство пользователя

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If the trace listing opcode column contains only
the words "dma long write (retry)" repeatedly
Check to see if the internal ribbon cable that connects the last sixteen channels of
the 80-channel internal analyzer to the HP 64783 emulator control board is missing.
If it is, locate the supplied ribbon cable and connect one end to the slot in the
analyzer board and the other end to the slot in the 68040 control board. Refer to
Chapter 19, "Installation and Service", in this manual to see the proper location of
this cable.
If the analyzer fails to trigger on a program
address
Check to make sure that the program address is a long-word address (an address
ending in 0, 4, 8, or C hex). The MC68040 fetches instructions on long-word
addresses. Other instruction addresses never appear on the processor bus, and
therefore are never seen by the analyzer. Modify the trigger address so that the two
least significant binary digits of your trigger address are zeroes. For example, to
trigger a trace on address 2316H, specify your trigger to occur on address 2314H.
Note that this only applies to instruction fetches; data reads and writes are made
directly to the destination address, regardless of whether it is a long-word address
or not.
If triggering on the occurrence of a program symbol, the above can be achieved by
including the long_aligned token in your trigger command.
Chapter 9: Solving Problems
If the trace listing opcode column contains only the words "dma long write (retry)" repeatedly
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