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SPNU563A–March 2018
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High-End Timer (N2HET) Module
Other instructions (MOV64, RADM64) can modify both the control and data fields of other instructions.
This allows the N2HET to implement toggle functionality. For example, an ECMP instruction can be
followed by a pair of MOV64 instructions. The MOV64 instruction updates the data field of the ECMP
instruction to implement the double buffering behavior. But it also updates the control field of the ECMP
instruction which allows it to change things like pin action and the conditional address. If one MOV64
instruction configures the ECMP pin action to SET while the second changes it to CLEAR, and the two
MOV64 instructions update the conditional address to point to each other, then a single ECMP instruction
can be used to toggle a pin each time the compare match occurs.
23.1.5 Performance
Most instructions execute in one cycle, but a few take two or three cycles.
The N2HET can generate many complex output waveforms without CPU interrupts. Where special
algorithms are needed following a specific event (for example, missing teeth or a short/long input signal), a
minimal number of interrupts to the CPU are needed freeing the CPU for other tasks.
23.1.6 N2HET Compared to NHET
N2HET enhancements from NHET include:
• Eight new instructions: ADD, ADC, SUB, SBB, AND, OR, XOR, RCNT
• Full set of ALU flags Carry (C), Negative (N), Zero (Z), Overflow (V)
• Branch instruction (BR) extended to support signed and unsigned arithmetic comparison conditions
• Two additional 32-bit temporary working registers R, S.
• New HETAND register for AND-Sharing of High Resolution structure between pairs of pins
• Improved high resolution PCNT instruction
23.1.7 NHET and N2HET Compared to HET
Compared to the HET module, the N2HET contains all of the enhancements described in Section 23.1.6
plus the following additional enhancements:
• New Interrupt Enable Set and Clear registers
• Capability to generate requests to the DMA module or the HET Transfer Unit (HTU) including new
Request Enable Set and Clear registers
• N2HET RAM parity error detection
• Suppression filters for each of the 32 I/O channel and control register to configure the limiting
frequency and counter clock
• Enhanced edge detection hardware that does not rely on the previous bit field in the control word of
the N2HET instruction.
• The next, conditional and remote addresses are extended from 8 to 9 bits
• The loop resolution data fields are extended from 20 to 25 bits
• The high resolution data fields are extended from 5 to 7 bits
• Instructions with an adequate condition are able to specify the number of the request line, which
triggers either the HET Transfer Unit (HTU) or the DMA module
• The CNT instruction provides a bit, which allows to configure either an equal comparison or a greater
or equal comparison when comparing the selected register value with the Max-value
• The MOV32 instruction provides a new bit. If set to one the MOV32 will only perform the move, when
the Z-flag is set. If set to zero the MOV32 will perform the move whenever it is executed (independent
on the state of the Z-flag)
• There is a new instruction WCAPE, which is a combination of a time stamp and an edge counter
• New Open Drain, Pull Disable, and Pull Select registers
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