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MC68306 USER'S MANUAL
MOTOROLA
Also, the MC68306 contains dynamic logic, so EXTAL must be driven by a free-running
clock at all times.
7.6 NON-IEEE 1149.1 OPERATION
In non-IEEE 1149.1 operation, the IEEE 1149.1 test logic must be kept transparent to the
system logic by forcing the TAP controller into the test-logic-reset state. This requires
either:
1. An active (low) signal applied to
TRST
.
2. A minimum of five consecutive TCK rising edges withh TMS high. TMS has an
internal pullup, and may be left unconnected.
If TMS either remains unconnected or is connected to VCC, then the TAP controller
cannot leave the test-logic-reset state, regardless of the state of TCK or
TRST
.