16-bit
From Wikipedia, the free encyclopedia
 |
This article does not cite any references or sources. (February 2008) Please help improve this article by adding citations to reliable sources. Unverifiable material may be challenged and removed. |
| Processors | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| 4-bit | 8-bit | 12-bit | 16-bit | 18-bit | 24-bit | 31-bit | 32-bit | 36-bit | 48-bit | 64-bit | 128-bit |
| Applications | |||||||||||
| 8-bit | 16-bit | 31-bit | 32-bit | 64-bit | |||||||
| Data Sizes | |||||||||||
| 4-bit | 8-bit | 16-bit | 32-bit | 64-bit | 128-bit | ||||||
| nibble byte octet word dword qword | |||||||||||
In computer architecture, 16-bit integers, memory addresses, or other data units are those that are at most 16 bits (2 octets) wide. Also, 16-bit CPU and ALU architectures are those that are based on registers, address buses, or data buses of that size.
[edit] 16-bit architecture
Prominent 16-bit processors include the PDP-11, Intel 8086, Intel 80286 and the WDC 65C816. The Intel 8088 was program-compatible with the Intel 8086, and was 16-bit in that its registers were 16 bits long and arithmetic instructions, even though its external bus was 8 bits wide.
A 16-bit integer can store 216 (or 65536) unique values. In an unsigned representation, these values are the integers between 0 and 65535; using two's complement, possible values range from −32768 to 32767. Hence, a processor with 16-bit memory addresses can directly access 64 KiB of byte-addressable memory.
16-bit processors have been almost entirely supplanted in the personal computer industry, but remain in use in a wide variety of embedded applications. For example the 16-bit XAP processor is used in many ASICs.
[edit] The 16/32-bit Motorola 68000
The Motorola 68000 is sometimes called "16-bit" because its data buses were 16 bits wide, however it was 32-bit in that the general purpose registers were 32 bits long and most arithmetic instructions supported 32-bit arithmetic, with up to 16 megabytes of addressable RAM. Thus the 68000 software is 32-bit in nature, and forwards-compatible with other 32-bit processors. The 68000 processor of the Sega Mega Drive/Genesis was a highly advertised feature of the video game system. Due to the saturation of this advertising, the 1988-1995 era of video game consoles is often called "the 16-bit era".
[edit] 16-bit File format
A 16-bit File format is a binary File format for which each data element is defined on 16 bits (or 2 Bytes). An example of such a format is the Windows Metafile Format.
