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ASCII World
SYN

Synchronous Idle

ControlASCII 22 | Hex 0x16 | U+0016
SYN (code 22) maintains synchronization on synchronous serial links. Unlike asynchronous communication (which uses start/stop bits per byte), synchronous links send continuous bit streams where the receiver must stay locked to the sender's clock. Idle lines transmit SYN characters to keep the clock synchronized. BSC protocol requires at least two SYN characters before the start of each message block. The name is unrelated to TCP SYN packets, which serve a different purpose at a higher protocol layer.

ASCII Code

Decimal
22
Hexadecimal
0x16
Octal
26
Binary
0001 0110

Unicode

Code Point
U+0016
Escape
\u0016
UTF-8 Hex
0xE2 0x90 0x96
UTF-8 Binary
111000101001000010010110
UTF-16
0x0016
UTF-32
0x00000016

HTML Entities

Numeric

Hex


How to Type

HTML Entity

Unicode InputU+0016

Source Code Representations

C / Java
"\u0016"
CSS
\0016
JavaScript
"\u0016"
Perl
\x{0016}
Python 2
u"\u0016"
Python 3
\u0016
Ruby
\u{0016}

Frequently Asked Questions

What is ASCII code 22?
ASCII code 22 represents the Synchronous Idle character. In hexadecimal it is 0x16, in binary 0001 0110, and in octal 26. This is a non-printable control character used for device signaling and data transmission control.
How do I type ASCII 22 on a keyboard?
Control characters are typically entered using Ctrl key combinations. For example, Ctrl+V produces ASCII 22 in most terminal emulators. You can also use the HTML entity  in web pages.