75XL Series

What are the limiting resistance and external capacitor constants when an external resonator is attached?

Evaluation of the resonator is performed by the resonator's manufacturer. Contact the manufacturer for this information.

Even though I have set the usage of the pull-up resistor to "unuse" via the emulation board's DIP switches, the voltage of approximately 3 V is output from the IE's input port's probe (EP-75008GB-R).

39 kΩ of pull-up resistance is used for the IE's input pin.
The combination of amount of pull-up resistance plus the resistance near the port and the probe's impedance are probably causing an intermediate potential.

Reference document:
IE-753000-R-EM User's Manual
  5.2 Handling of Pins of IE-75300-R-EM (uPD750008 and 0108 Subseries)

When I execute the STOP instruction in the uPD75P0016, where does the program counter stop?

It stops at the next location following execution of the STOP instruction.

Can a program developed for the uPD75P108 be used without modification in the uPD75P108B?

75P108B        75P108     (unit) ------------------------------------------------------------------- PROM size          8064          8192     Bytes Power supply voltage         2.7 to 6.0      4.5 to 5.5   V Temperature range           -40 to +85      -10 to +85    °C Vpp                     12.5 21         V

Programs that are functionally identical can be used in both devices.
However, note with caution that the ROM size differs between the uPD75P108 and uPD75P108B.
In addition, these two devices have slightly different noise characteristics.
Accordingly, each device should be checked in the system where it is used. The main differences between the uPD75P108 and uPD75P108B are listed at right.

Two types of split resistors for driving the uPD753012A's LCD can be selected as mask options: 10 kΩ and 100 kΩ. It would seem that the 100-kΩ resistor would be better, considering the current consumption. What is the advantage of using a resistor with the lower resistance?

The lower resistance improves the display's quality.
Although this must be balanced against other LCD characteristics, when the capacitance components of the wiring and display block are large, it can result in waveform degradation. A degraded waveform reduces the display's quality. When a split resistor with the lower resistance is used, the degradation in waveform for the display elements that have a larger capacitance is comparatively improved.

The high-level input voltage for INT0 (P10) is:
  MIN: 0.8VDD, MAX: VDD
Is this the same even when interrupt detection (at the rising edge) is used?

Whether for an interrupt or a port, the input level to this pin has the same rated value.
Section "3.3 Pin I/O Circuits" of the data sheet notes that there is a hysteresis buffer for this input. Since the input buffer cannot be split by any function, the same judgment level is used.

Is the uPD75304 upwardly compatible with any other products?

There are no newer products that can use uPD75304's programs without modification.
The closest product to the uPD75304 in terms of functions is the uPD753012A, which is an expanded-function product in the 75XL Series. However, due to the uPD753012A expanded function, it cannot use the uPD75304's programs as they are; the programs must be checked and modified using development tools.

Can the EVAKIT-7500 or EVAKIT-75X be used for 75XL development?

Since the 75XL features an expanded (64 Kbytes) address space, the EVAKIT-7500 and EVAKIT-75X cannot be used for 75XL development.

When an external clock is used to operate the uPD75P3116, is it OK if the microcontroller's power supply voltage differs from the clock driver's power supply voltage?
(Microcontroller: 4 V, clock driver: 5 V)

No, that is not OK.
We recommend adjusting the clock driver's power supply voltage to match the microcontroller's. Also, use a clock driver that is able to use an input voltage that exceeds the power supply voltage.

(Supplement)
The microcontroller's absolute maximum rating for input voltage is 0.3 V to VDD + 0.3 V. Accordingly, voltage up to 4.3 V can be applied to the clock pin in the case you cited in your question.
The clock pin's DC characteristics are:
  VIH4 (X1 pin): VDD 0.1 V to VDD
  VIL3 (X1 pin): 0 V to 0.1 V

Can 150-kHz frequency be generated in a 4-bit microcontroller by a software timer?

No, software cannot generate such a timer. Use the internal hardware instead.
However, instead of a timer, a clock output circuit (pin name: PCL) that outputs a clock by dividing the main system clock frequency is used. The main system clock's oscillation frequency has to be changed to realize 150-kHz frequency.
        The division ratios are 64, 16, and 8.
The 75XL Series products in which this has been confirmed are:
754302, 750004, 753204, 753104, 753012, and 753036.
Check the specification table to determine the oscillation frequency range. Even when the frequency is within the oscillation frequency range, evaluation of the resonator may be necessary for certain special frequencies.

Are there any ROM programmers that support the uPD75P54, uPD75P64, or uPD75P008CU?

In the past, the following products have been available, although their current availability is uncertain since these are older products. Check with the sales outlets that handle such products, as well as programmer manufacturers.
- For 75P54 or 75P56

NEC Programmer: PG-1500 Adapter: PA-75P54CS	Ando Electric (Tel: 03-3733-1166)     AF-9703, 9704, etc
	Data IO Japan (Tel: 03-3779-2153)   UNISITE, 2900, 3900, etc.

Contact the manufacturer for details.

- For uPD75P008CU

NEC Programmer: PG-1500 Adapter: PA-75P008CU

The manufacturers noted above may have products for this. Check with the manufacturer.