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of the two clipsout lines. These are output from the PICE system and are initially low. Then,
enter the GO command for each probe. Each probe hangs after the first instruction fetch.
Then, set the clipsout line to 1. All the probes enter emulation simultaneously.
The 80286 Probe
SYNC START/ is normally high. When SYNC START/ is low and the probe enters emulation,
the probe treats SYNC START/ as an auxiliary hold input (HLDA will not be activated).
HOLD is asserted and the 80286 no longer has access to the address and data buses.
To synchronize the probes in a multiple-probe system, first set the BUSACT and MEMRDY
pseudo-variables to FALSE in each probe. This prevents a bus time-out from occurring when
the 80286 microprocessor loses control of the address and data buses. Then, keep SYNC
START/ on each probe low and ensure that SYNC START/ for each probe goes high at the
same time. This lowers HOLD (de-asserts it) and returns the address and data buses to the
80286 microprocessor, allowing emulation to proceed. In this way you can ensure that each
probe enters emulation at the same time.
Multiple-Probe Systems
6-7/6-8
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