CHAPTER 10

SPECIAL OPERATING MODES

The 8XC196Lx’s idle and powerdown modes are the same as those of the 8XC196Kx. However, the clock circuitry has changed, and the on-circuit emulation (ONCE) special-purpose mode op- eration has changed slightly because of the new reset state pin levels that have been implemented.

10.1 INTERNAL TIMING

The 87C196LA and LB clock circuitry (Figure 10-1) implements a phase-locked loop and clock multiplier circuitry, which can substantially increase the CPU clock rate while using a lower-fre- quency input clock.

10-1

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Intel 87C196CA, 8XC196Jx, 8XC196Lx, 8XC196Kx user manual Chapter Special Operating Modes, Internal Timing