Intel Microcontroller manual Extended Indirect Addressing, Indirect Addressing with Autoincrement

Models: Microcontroller 80C196NU 8XC196NP

1 471
Download 471 pages 22.3 Kb
Page 65
Image 65

8XC196NP, 80C196NU USER’S MANUAL

LD

AX,[BX]

; AX

MEM_WORD(BX)

ADDB

AL,BL,[CX]

;

AL

BL + MEM_BYTE(CX)

POP

[AX]

;

MEM_WORD(AX) MEM_WORD(SP)

;SP SP + 2

4.2.3.1Extended Indirect Addressing

Extended load and store instructions can use indirect addressing. The only difference is that the register containing the indirect address must be a word-aligned 24-bit register to allow access to the entire 1-Mbyte address space. The following instructions use extended indirect addressing:

ELD

AX,[EX]

; AX MEM_WORD(EX)

ELDB AL,[EX]

; AL MEM_BYTE(EX)

EST

AX,[EX]

;

MEM_WORD(EX)

AX

ESTB AL,[EX]

;

MEM_BYTE(EX)

AL

4.2.3.2Indirect Addressing with Autoincrement

You can choose to automatically increment the indirect address after the current access. You spec- ify autoincrementing by adding a plus sign (+) to the end of the indirect reference. In this case, the instruction automatically increments the indirect address (by one if the destination is an 8-bit register or by two if it is a 16-bit register). When your code is assembled, the assembler automat- ically sets the least-significant bit of the indirect address register. The following instructions use indirect addressing with autoincrement:

LD

AX,[BX]+

; AX

MEM_WORD(BX)

 

 

; BX

BX + 2

ADDB

AL,BL,[CX]+

; AL

BL + MEM_BYTE(CX)

 

 

;

CX

CX

+

1

PUSH

[AX]+

;

SP

SP

-

2

;MEM_WORD(SP) MEM_WORD(AX)

;AX AX + 2

4.2.3.3Extended Indirect Addressing with Autoincrement

The extended load and store instructions can also use indirect addressing with autoincrement. The only difference is that the register containing the indirect address must be a word-aligned 24-bit register to allow access to the entire 1-Mbyte address space. The following instructions use ex- tended indirect addressing with autoincrement:

ELD

AX,[EX]+

; AX MEM_WORD(EX)

 

 

; EX EX + 2

ELDB AL,[EX]+

; AL MEM_BYTE(EX)

 

 

; EX EX + 2

EST

AX,[EX]+

; MEM_WORD(EX) AX

 

 

; MEM_WORD(EX) MEM_WORD(EX + 2)

ESTB AL,[EX]+

; MEM_BYTE(EX) AL

 

 

; MEM_BYTE(EX) MEM_BYTE(EX + 2)

4-8

Page 65
Image 65
Intel Microcontroller, 80C196NU, 8XC196NP manual Extended Indirect Addressing, Indirect Addressing with Autoincrement

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.