Recourse If the content of 2 bytes adjacent to each other in memory is 74 and 51 in hexadecimal form

GB code. It is the standard encoding of Chinese character information exchange, but because the highest bit of the byte before and after it is 0, it conflicts with the ASCII code, such as the word "Bao", the national standard code is 31h and 23h, and the scii of the Western characters "1" and "" is also 31h and 23h, now if there are two bytes in the memory for 31h and 23h,; Is this one Chinese character or two Western characters "1"; and " "?".So there is ambiguity, obviously, the national standard code is not possible to be directly adopted inside the computer, so,; The in-machine code of Chinese characters adopts the deformed national standard code, and its transformation method is:

Add 128 to each byte of the national standard code, that is, the highest bit of the two bytes is changed from 0 to 1, and the remaining 7 bits remain unchanged, such as: from the above we know that the national standard code of the word "Bao" is 3123h, the first byte is 00110001b, the last byte is 0010001b, and the high position is changed to 10110001b and 10100011b is b1a3h, therefore, the machine code of the word is b1a3h;.

Obviously, each byte of the Chinese character in-machine code is greater than 128, which solves the problem of conflict with the ASCII code of Western characters.

Because kanji are represented by two bytes, in order to distinguish kanji from other character sets (English, Japanese, etc.).

Generally, the scope is divided.

And the range of Chinese characters is:

Name First Byte Second Byte.

gb2312 0xb0-0xf7(176-247) 0xa0-0xfe（160-254）

gbk 0x81-0xfe（129-254） 0x40-0xfe（64-254）

big5 0x81-0xfe（129-255） 0x40-0x7e（64-126）0xa1－0xfe（161-254 ）

And 0x74 and 0x51 are not in this range.

When the data is stored in the memory, it is generally followed that there is a low address in the low byte and a high address in the high byte, so the hexadecimal number 12345678h is in descending order according to the byte address: 78h 56h 34h 12h.

0xffff+1 (0~ffff)

0x10000

65536 bytes.

Introduction to 64kb The hexadecimal system is briefly outlined above, such as the decimal number 57, written 111001 binary, and written 39 in hexadecimal. Today's decimal hexadecimal system is commonly used in computer applications because it is not too difficult to convert 4 bits into individual hexadecimal numbers. 1 byte can be represented as 2 consecutive hexadecimal digits.

However, this hybrid notation can be confusing, so it requires some initials, endings, or subscripts to display.

If you don't specify the make, model, and model of the CPU, it's empty talk to talk about its data storage.

If the contents of the next 2 bytes in the PC memory have the hexadecimal form 74 and 51, they cannot be the internal code. The characteristics of the Chinese character machine internal code are: the highest bit of the two bytes, both are 1.

And the highest digit is 0, so it can't be the in-machine code.

Due to historical and regional reasons, sometimes there are multiple encoding schemes for one script, especially Chinese characters. Because the characters that are different from the internal code of the system cannot be displayed normally in the system, it is necessary to convert the internal code of the characters, that is, the characters that are not the internal code of the system are converted into the internal code characters that can be recognized by the system.

NJStar is such an excellent software, and other internal code conversion tools such as Sitong Lifang, magicwin98, cross-strait communication, Chinese character communication, etc.

If each byte of the internal code is greater than 128, that is, 80h, and 74 and 51 are less than 80, it cannot be the internal code.

The characteristics of the Chinese character machine internal code are: the highest bit of the two bytes, both are 1. And the highest digits of are all 0, so it can't be.

Because the Chinese character processing system should ensure the compatibility of Chinese and Western languages, when there are ASCII codes and Chinese national standard codes in the system at the same time, ambiguity will occur. For example, if there are two bytes of content for 30h and 21h, it can represent both the national standard code of the Chinese character "ah" and the western word "0" and "!".

ASCII code. For this reason, the Chinese character machine code should be properly processed and transformed into the national standard code.

Each byte of the internal code is greater than 128, that is, 80h, 74 and 51 are less than 80, of course, it cannot be the internal code! Right?

To die for, ask such a deep question,

Usually the n-bit binary, the highest bit is the sign bit, the positive sign bit is 0, and the negative sign bit is 1;

Find the complement of a positive complement.

The complement of a positive number is the same as the original code.

Complement of a negative number.

The complement of a negative number is equal to its sign bit unchanged, the inversion of the numeric part, and then the whole number is added by 1.

If it's a positive number.

If the sign bit is 0, the complement is 00011111

The original code is also 00011111

This number (the smallest) is.

1) 0*(2 4+2 3+2 2+2 1+1)=31 if it is negative.

If the sign bit is 1, the complement is 10001111

The original code is 11110001

This number (the smallest) is.

The highest digit of the two bytes of a Chinese character machine code must be 1, and 36h and 46h are not.

There are only two below.

b1h, d2h, is one;

c8h, b4h, and another one.

A kanji is two bytes larger than a0h. So, 6ah and 53h are not Chinese characters (lowercase j and uppercase s, respectively), while b1d2h and c8b4h are Chinese characters.

A Chinese character is represented by two bytes, so 6 bytes can represent three Chinese characters. The first GB2312 code is BAB1, and the corresponding Chinese character is "han" when looking up the table; the second d2c3, which corresponds to the Chinese character "颐"; The third c8b4 corresponds to the Chinese character "but".

Answer]: b The inner code of the Chinese character = the national standard code of the Chinese character + 8080h So the highest digit of the inner code of the Chinese character is 1.

This memory has a capacity of 64k, and the answer is (c).

Because the address code is from 0000-ffff, the largest address number is ffff, which is converted into a decimal number of 65536, which is the largest address range of the memory. The capacity of memory refers to the maximum number of units of information that can be stored in a piece of memory. Here it is 65,536, so in a computer, the capacity of this memory can be expanded up to 64k.

In the MCS-51, the program memory is addressed by a 16-bit program counter (PC), which has 64KB addressing capability, that is, it can be arbitrarily addressed in the 64KB address space.

Among them, it has 4KB of on-chip program memory space, and the address is 000H-0FFH (Note: 8031 does not have on-chip program memory); The off-chip program memory space can be expanded to a maximum of 64KB, and the address is 0000h-ffffh, and the on-chip and off-chip are uniformly addressed.

Get: x1=-4*3=-12

From the known solution: x2=x1-5=-12-5=-17 of equation 2 substitutes x2 into the equation, which is: 6*(-17)-a=0, i.e.: z=6*(-17)=-102

Substituting a into Equation 3 gives us -102 x-2 51=0, i.e.: -102 x=2 51

x=-102*51/2=-601

It should be a... Because the ASCII code of Western characters is a minimum of 41h.

Select B, the in-camera code for a Chinese character.

Summary. Hello dear, a byte = 8-bit binary number, the maximum is 11111111, if this number is carried to the eighth power of 2, that is, 256, so the maximum is 255. If the smallest integer is required, it must be 0; The smallest positive integer, that's 1

5.If you use one byte to represent a meta-symbolic decimal integer, and the highest and lowest digits are set.

Hello dear, a byte = 8 bits binary number, the largest is 11111111, if this number is carried on the eighth power of 2 Xianzhou, that is, 256, so the maximum is 255. If the smallest integer is required, it must be 0; The smallest positive integer brother is 1

Hello dear, the answer is as follows If you use a byte to represent an integer, the highest bit is used as a sign bit, and the other bits represent numerical values. In this way of encoding, the range is -127 a 127, and there are only two encodings for only one number in the range. So chosen:

d。Analyze the characteristics of binary ** regret three characteristics:1 There are two basic data bi short:

0 and 12 adopt the principle of carrying every two to one3 Each number corresponds to a different weight in a different digit