Intel 8XC196MC Microscope & Magnifier User Manual


 
8XC196MC, MD, MH USER’S MANUAL
B-16
EPA3:0 (MC)
EPA5:0 (MD)
EPA1:0 (MH)
I/O Event Processor Array (EPA) Capture/Compare Channels
High-speed input/output signals for the EPA capture/compare channels.
EPA5:0 are multiplexed as follows: EPA0/P2.0/PVER, EPA1/P2.1/PALE# (MC,
MD), EPA1/P2.2/PROG# (MH), EPA2/P2.2/PROG#, EPA3/P2.3, EPA4/P7.0,
and EPA5/P7.1.
EPA5:4 are not implemented on the 8XC196MC and EPA5:2 are not
implemented on the 8XC196MH.
EXTINT I External Interrupt
This programmable interrupt is controlled by the WG_PROTECT register. This
register controls whether the interrupt is edge triggered or sampled and whether
a rising edge/high level or falling edge/low level activates the interrupt.
In powerdown mode, asserting the EXTINT signal for at least 50 ns causes the
device to resume normal operation. The interrupt need not be enabled. If the
EXTINT interrupt is enabled, the CPU executes the interrupt service routine.
Otherwise, the CPU executes the instruction that immediately follows the
command that invoked the power-saving mode.
In idle mode, asserting any enabled interrupt causes the device to resume
normal operation.
FREQOUT
(MD only)
O Frequency Generator Output
A fixed 50% duty cycle waveform that can vary in frequency from 4 KHz to 1
MHz (assuming F
XTAL1
= 16 MHz).
FREQOUT is multiplexed with P7.7.
FREQOUT is not implemented on the 8XC196MC or MH.
INST O Instruction Fetch
This active-high output signal is valid only during external memory bus cycles.
When high, INST indicates that an instruction is being fetched from external
memory. The signal remains high during the entire bus cycle of an external
instruction fetch. INST is low for data accesses, including interrupt vector
fetches and chip configuration byte reads. INST is low during internal memory
fetches.
INST is multiplexed with P5.1.
NMI I Nonmaskable Interrupt
In normal operating mode, a rising edge on NMI generates a nonmaskable
interrupt. NMI has the highest priority of all prioritized interrupts. Assert NMI for
greater than one state time to guarantee that it is recognized.
Table B-6. Signal Descriptions (Continued)
Name Type Description