HARDWARE OVERVIEW

3.8LCD INTERFACE

The evaluation board includes a 16-character by 1-line LCD display. The display has an 8-bit interface and is designed to operate at up to 20 MHz. The display includes a Hitachi* 44780 LCD display controller that takes care of functions such as character interpretation and display refresh.

The display is write-only. This is because the display controller operates at 5 volts VCC. A 5-volt part driving a 3.3-volt bus can damage parts operating at 3.3 volts VCC. This means that the BUSY pin of the processor cannot be monitored to determine when the processor is ready for the next command, so a delay loop must be used to allow the display to finish commands.

Signals from the 80x186 processor can be connected directly to the LCD controller inputs, regardless of VCC, because 3.3 volt and 5 volt outputs are compatible with 5 volt TTL level inputs.

The LCD display is mapped in I/O space at 400H to 440H. All command and data writes to the display are to this address. Port pin 1.4 is used to control which LCD register is accessed. P1.4 = 0 accesses the command register; P1.4 = 1 accesses the data register.

3.8.1LCD Interface Demo

The diskette provided in your kit includes a file, LCD_DEMO.ASM, that contains source code you can assemble and load onto the board (using iECM). You can execute the program for a demonstration of the basic principals of operating the LCD display module. This program prints a static message to the display. The source code is commented to serve as a tutorial and can be adapted as needed for other applications and messages. Note that although the LCD module is capable of displaying standard ASCII (characters 32 through 125) or custom characters, this demo uses only ASCII characters.

For more information regarding the operation of the display controller, please refer to the Hitachi LCD Controller/Driver LSI Data Book.

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Intel 80C186EC, 80L188EC, 80L186EB, 80L186EC, 80C186EB, 80C188EB, 80L188EB, 80C188EC user manual LCD Interface Demo

80L188EB, 80C188EC, 80C188EB, 80L186EB, 80C186EB specifications

The Intel 80L188EC, 80C186EC, 80L186EC, 80C186EB, and 80L186EB microprocessors represent a significant evolution in Intel's 16-bit architecture, serving various applications in embedded systems and computing during the late 1980s and early 1990s. These microprocessors are designed to offer a blend of performance, efficiency, and versatility, making them suitable for a range of environments, including industrial control, telecommunications, and personal computing.

The Intel 80L188EC is a member of the 186 family, notable for its low-power consumption and integrated support for a range of peripheral devices. It operates at clock speeds of up to 10 MHz and features a 16-bit architecture, providing a balance of processing power and energy efficiency. The 80C186EC, on the other hand, is a more advanced version, offering enhanced performance metrics with faster clock speeds and improved processing capabilities, making it ideal for applications that require more computational power.

The 80L186EC shares similarities with the 80L188EC but is enhanced further for various low-power applications, especially where battery life is crucial. With a maximum clock speed of 16 MHz, it excels in scenarios demanding energy-efficient processing without sacrificing performance.

In contrast, the 80C186EB and 80L186EB are optimized versions that bring additional features to the table. The 80C186EB operates at higher clock speeds, coupled with an extended instruction set, enabling it to handle more complex tasks and run sophisticated software. These enhancements allow it to serve well in environments that require reliable performance under load, such as data acquisition systems or advanced control systems.

The 80L186EB is tailored for specific low-power scenarios, integrating Intel's sophisticated low-power technologies without compromising on speed. Utilizing advanced process technologies, these chips benefit from reduced heat output and extended operating life, a significant advantage in embedded applications.

Overall, these microprocessors showcase Intel's commitment to innovation in 16-bit processing, marked by their varying capabilities and power profiles tailored to meet the demands of diverse applications, from industrial systems to consumer electronics. Their legacy continues to influence subsequent generations of microprocessor designs, emphasizing performance, energy efficiency, and versatile applications in computing technology. As such, the Intel 80C186 and 80L188 families play a crucial role in understanding the evolution of microprocessor technology.