The data type of the verilog expression

1.The decimal system of 15 can be represented as 4 as 4 bits'B1111 (binary), 4'd15 (decimal), or 4'hf (hexadecimal).That is, it should correspond to the base system.

4'B15 is absolutely wrong, because there are only 1s and 0s in binary.

h98 is not a decimal 98, but a hexadecimal, that is, 9*16+8=152 in decimal

And 3'd98 is 98 in decimalIf you write 98 directly, the default is 98 in decimal. If there are more digits, the high digit will be zero, and if the number of digits is less, it will be truncated.

Addendum: The hardware is all in binary, just for convenience can be expressed in decimal. Since you use Verilog, you have to have hardware thinking, hehe.

The different decimal systems in verilog are represented by different letters, b for octal, d for decimal, h for hexadecimal, and commonly used for binary and hexadecimal, 4'd15 is the decimal number 15, but it is stored in binary form, such as the decimal number 15, which can be written as 4'd15, which can also be written as 4'b1111。Hope you can help you.

4'B1111 can be expressed as 4'The representation of d15,4'b15 is wrong. b stands for binary and d stands for decimal.

Always is not a loop statement, always is a process block. always@ (a or b or c) We can often see the always statement such as the above sentence, when the a, b or c signal in parentheses changes, the always module is activated, and the statement in the module can be executed. The signals in parentheses are called the list of sensitive signals.

All the always-blocks have a parallel relationship with each other, and who is first and who is last does not affect the order of execution.

for is a circular statement, but it cannot be synthesized (compiled). for is usually used in test files. Or it can be used to attach an initial value to the RAM. For example, a RAM space is defined.

reg [n-1:0] mem [word-1:0];

You can use a for loop when initializing.

integer i;

for(i=0;In this way, all the contents of RAM are defined as 0. However, for cannot be used in circuit entities.

Verilog is a hardware description language, used to describe the structure and behavior of hardware, not software, not C, very different, there is no such thing as loops. It can be said that the program made by verilog is actually the same thing as the drawing of hardware engineers, each statement, each module, represents the use of a chip, and then connected to the line so that the hardware circuit comes from the loop, pay attention to the good difference.

A type of hardware description language that describes chips and hardware implementations.

FPGA-based development language is a hardware description language.