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4

Arduino code expects Arduino clocks. If it has 16 MHz clock, it will run half as fast as it does not know that you are in fact using 8MHz clock. Apparently the boards.txt file contains board build configurations including the board clock that gets passed on as F_CPU define for building all libraries, so adding a new custom board entry should be enough for ...


4

Intel put out the 8086 Family User's Manual quite some time ago. (1978 and 1979.) It includes AP-67 and a datasheet on the processor, too. You can get all of these from this bitsavers site link in a single PDF file. I'm a little taken aback that you didn't bother looking for Intel documentation on their own processors in order to answer your own questions ...


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This seems to be covered in section 2.3 of the datsheet: No external termination is required for unused inputs. If you want to use external termination to improve noise immunity, pull the true input down and the complementary input up. Tie /CLK1 to VDD/2 by connecting it to the same voltage divider as /CLK0 (considering the case of single ended CMOS ...


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Clocked logic elements are built from pairs of latches. We’ll call them Stage 1 and Stage 2. (Often they’re called master and slave, but I dislike those terms and avoid them when I can.) A basic clocked flop works like this: Stage 1 latch passes input during clock-low time and holds during clock high Stage 2 latch passes input during clock-high time and ...


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In addition to @Bimpelrekkie's answer, you should know that the clock signal may be buffered and inverted inside the flip-flop. So there are internal clock signals that may not be in their final stable states at the instant that the external clock rises. The "hold" time ensures that the input data remains valid until all of the internal clock signals have ...


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Why is the original intended circuit as seen in Conditions A & B not allowing the counter register to count to the desired value and resetting at [n-1]? The resulting 1 from the comparator resets the counter asynchronously. That means, it does not need a rising edge. Thus the comparator part of the circuit never outputs 1 […] This is not correct. ...


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It is never OK to leave inputs to a chip open unless the data sheet for the part specifically says that it is OK. Generally the reason that a chip data sheet may say it is permissible to leave an input open is that there chip designer has allowed for there to be an onchip weak pullup or pulldown on the pin. However even with this convenience from the chip ...


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All circuits have delays due to (parasitic) capacitances which need to be (dis)charged. The (dis)charging is done through switches (usually transistors) which do not have a zero series resistance. This means that the speed of any change is limited by at least some RC timing constant. The hold time is needed because the flip flop isn't infinitely fast. It ...


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