Specifications

Signal Simulation Characteristics 67
Probing a Pin
If the probe tip is clicked on a device pin close to the device body, the
probe shows the driving level of that pin, rather than the state of the
attached signal. This can be used to resolve drive conflicts in multiple drive
situations, as in the following example using open collector buffers:
NOTE: The probe display does not distinguish between low and high drive levels.
Injecting a Value Using the Probe Tool
While the mouse button is held, you can press keys on the keyboard to
inject new values onto a signal, as follows:
If a stuck value is forced onto a signal, the signal will not change state until
the stuck value is cleared by some user action, regardless of device outputs
Pin Drive on Upper Device Pin Drive on Lower Device Combined Signal Value
0LOW.F
1HIGH.F
X DONT01.F
C CONF.F
ZHIGHZ
L LOW.F stuck
HHIGH.F stuck
space unstick
LW Reference.bk Page 67 Monday, December 15, 2003 5:59 PM