base 10 |
The most commonly used number system in everyday life, also known as the decimal system. Each position in a base ten number represents a power of 10. The base 10 system uses ten digits, 0-9. |
base 16 |
A commonly used numbering system for PLCs, also known as hexadecimal. Each position in a base 16 number represents a power of 16. Base 16 uses 16 characters: 0 through 9 and A through F. |
base 2 |
The most commonly used number system in PLCs and other computer systems, also known as the binary system. Each position in a base 2 number represents a power of 2. The base 2 system has only 2 characters, 0 and 1. |
base 8 |
A commonly used numbering system for PLCs, also known as octal. Each position in a base 8 number represents a power of 8. Base 8 only uses 8 characters, 0 through 7. |
BCD |
Binary-coded decimal. A binary-based code in which each decimal digit from 0 to 9 is represented by four binary bits. |
binary |
The most commonly used number system in PLCs and other computer systems, also known as the base 2. Each position in a binary number represents a power of 2. The binary system has only 2 characters, 0 and 1. |
binary-coded decimal |
BCD. A binary-based code in which each decimal digit from 0 to 9 is represented by four binary bits. |
bit |
Each position in a binary number. A bit may be a 0 or a 1. |
bit strings |
Consecutive groups of binary bits. |
byte |
A binary number made of 8 consecutive bits. |
consecutive binary bits |
Binary bits that fall after one another that may be used individually or as a group. |
data type |
A description of a bit string pattern in a PLC that shows how the PLC interprets the bit string. |
decimal |
A numbering system that uses ten digits, from 0 to 9, arranged in a series of columns to represent all numerical quantities. Each column or place value has a weighted value of 1, 10, 100, 1000, and so on, ranging from right to left. |
DInt |
Signed double integer. A type of integer used by a Siemens PLC that is 32 bits long. A signed double integer may have any decimal value between -2,147,483,648 to +2,147,483,647. |
hexadecimal |
A commonly used numbering system for PLCs, also known as base 16. Each position in a hexadecimal number represents a power of 16. Hexadecimal uses 16 characters: 0 through 9 and A through F. |
Int |
Signed integer. A type of integer used by a Siemens PLC that is 16 bits long. A signed integer may have any decimal value between -32,768 and +32,767. |
integer |
A positive or negative whole number. |
least significant bit |
LSB. In a binary number, the bit farthest to the right. |
Lreal |
Long real number. A type of real number that some SIMATIC PLCs can use that has 64 bits. |
LSB |
Least significant bit. In a binary number, the bit farthest to the right. |
mantissa |
The part of a floating-point number that represents the value that is multiplied by a power of ten. |
most significant bit |
MSB. In a binary number, the bit farthest to the left. |
MSB |
Most significant bit. In a binary number, the bit farthest to the left. |
octal |
A commonly used numbering system for PLCs, also known as base 8. Each position in an octal number represents a power of 8. Octal only uses 8 characters, 0 through 7. |
power |
A mathematical notation indicating the number of times a quantity is multiplied by itself. Also known as an exponent. |
Real |
A type of real number that a SIMATIC PLC can use that has 32 bits. |
real numbers |
A number that consists of a manitssa that is multiplied a power of 10 to arrive at the actual value. |
scientific notation |
A system of writing numbers that involves converting them to a mantissa multiplied by a power of ten. |
signed |
Indicates that a number can have a positive or negative sign. |
signed double integer |
DInt. A type of integer used by a Siemens PLC that is 32 bits long. A signed double integer may have any decimal value between -2,147,483,648 to +2,147,483,647 |
signed integer |
Int. A type of integer used by a Siemens PLC that is 16 bits long. A signed integer may have any decimal value between -32,768 and +32,767. |
signed short integer |
SInt. A type of integer used by a Siemens PLC that is 8 bits long. A signed short integer may have any decimal value between -128 and +127. |
SInt |
Signed short integer. A type of integer used by a Siemens PLC that is 8 bits long. A signed short integer may have any decimal value between -128 and +127. |
two’s complement |
A system for writing negative numbers in binary in which the pattern of bits used to store a negative binary number is determined by inverting all the binary bits in the equivalent positive binary value and then adding a binary 1. |
UDInt |
Unsigned double integer. A type of integer used by a Siemens PLC that is 32 bits long. Unsigned double integers may have any decimal value between 0 and 4,294,967,295. |
UInt |
Unsigned integer. A type of integer used by a Siemens PLC that is 16 bits long. Unsigned integers may have any decimal value between 0 and 65,535. |
unsigned |
Indicates that a number can only represent 0 or positive numbers. |
unsigned double integer |
UDInt. A type of integer used by a Siemens PLC that is 32 bits long. Unsigned double integers may have any decimal value between 0 and 4,294,967,295. |
unsigned integer |
UInt. A type of integer used by a Siemens PLC that is 16 bits long. Unsigned integers may have any decimal value between 0 and 65,535. |
unsigned short integer |
USInt. A type of integer used by a Siemens PLC that is only 8 bits long. Unsigned short integers can have any decimal value between 0 and 255. |
USInt |
Unsigned short integer. A type of integer used by a Siemens PLC that is only 8 bits long. Unsigned short integers can have any decimal value between 0 and 255. |