8XC196NP, 80C196NU USER’S MANUAL

When the next timer match occurs, the PTS cycle (Figure 6-16) increments EPA0_TIME by T1 (if TBIT is zero (output = 0)) or T2 – T1 (if TBIT is one (output = 1)). (Note that although the values of the EPA0 output and TBIT are the same in this example, these two values are unrelated. To establish the initial value of the output, set or clear P1_REG.x.)

The PWM toggle mode has the advantage of using only one EPA channel. However, if the wave- form edges are close together, the PTS may take too long and miss setting up the next edge. The PWM remap mode uses two EPA channels to eliminate this problem.

6.6.5.2PWM Remap Mode Example

Figure 6-17 shows the PTS control block for PWM remap mode. The following example uses two EPA channels and a single timer to generate a PWM waveform in PWM remap mode. EPA0 as- serts the output, and EPA1 deasserts it. For each channel, an interrupt is generated every T2 pe- riod, but the comparison times for the channels are offset by the on-time, T1 (see Figure 6-14 on page 6-27). Although TBIT is toggled at the end of every PWM remap mode cycle (see Table 6-7 on page 6-26), it plays no role in this mode. To generate a PWM waveform, follow this procedure.

1.Disable the interrupts and the PTS. The DI instruction disables all interrupts; the DPTS instruction disables the PTS.

2.Set up one PTSCB for EPA0 and one for EPA1 as shown in Table 6-9. Note that the two blocks are identical, except that PTSPTR1 points to EPA0_TIME for EPA0 and to EPA1_TIME for EPA1.

3.Configure P1.1 to serve as the EPA1 output. (Because EPA0 is not used as an output, port pin P1.0 can be used for standard I/O.)

Clear P1_DIR.1 (selects output).

Set P1_MODE.1 (selects the EPA0 special-function signal).

Set P1_REG.1 (initializes the output to “1”).

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Intel 8XC196NP, 80C196NU, Microcontroller manual PWM Remap Mode Example

Microcontroller, 80C196NU, 8XC196NP specifications

The Intel 8XC196NP and 80C196NU microcontrollers are part of Intel's renowned 16-bit microcontroller series that gained popularity in the 1980s and 1990s for embedded systems applications. Designed for a variety of applications, these microcontrollers are characterized by their robust performance, versatility, and industry-standard architecture.

The 8XC196NP features an enhanced instruction set with over 100 instructions, allowing for efficient code execution. It operates at clock speeds up to 16 MHz, which contributes to improved performance in time-sensitive applications. The microcontroller is equipped with a 16-bit data bus, enabling more efficient data handling compared to its 8-bit predecessors, thus accommodating complex algorithms and large data sets.

In terms of memory architecture, the 8XC196NP supports an addressable memory space of up to 64 KB of program memory and 64 KB of data memory. This configuration provides sufficient space for large applications while ensuring fast data access. The microcontroller includes integrated features such as timers, serial I/O capabilities, and interrupt processing, which enhance its functionality for real-time applications and control mechanisms.

The 80C196NU, on the other hand, is designed for lower power operation, making it suitable for battery-powered devices. This microcontroller maintains similar features to the 8XC196NP while offering advancements that support low-power consumption. The 80C196NU can also function in a range of temperature environments, making it adaptable for industrial applications.

Both the 8XC196NP and 80C196NU support external memory interfacing, allowing designers to expand the system's capability by connecting additional ROM and RAM. This flexibility makes them appealing for developing complex systems, such as motor controls, industrial automation, and consumer electronics.

Another standout feature of these microcontrollers is their built-in debugging capabilities. Intel provided hardware and software tools that enabled developers to test and troubleshoot their applications effectively, reducing the development time and increasing reliability.

Overall, the Intel 8XC196NP and 80C196NU microcontrollers stand out for their dependability, versatility, and performance, contributing significantly to the evolution of embedded system design. Their legacy continues to influence modern microcontroller technology, ensuring their relevance in a wide array of applications today.