C6x

Texas Instruments TMS320 is a blanket name for a series of digital signal processors (DSPs) from Texas Instruments. It was introduced on April 8, 1983 through the TMS32010 processor, which was then the fastest DSP on the market.

The processor is available in many different variants, some with fixed-point arithmetic and some with floating point arithmetic. The floating point DSP TMS320C3x, which exploits delayed branch logic, has as many as three delay slots.

The flexibility of this line of processors has led to it being used not merely as a co-processor for digital signal processing but also as a main CPU. Newer implementations support standard IEEE JTAG control for boundary scan and/or in-circuit debugging.

The original TMS32010 and its subsequent variants is an example of a CPU with a modified Harvard architecture, which features separate address spaces for instruction and data memory but the ability to read data values from instruction memory. The TMS32010 featured a fast multiply-and-accumulate useful in both DSP applications as well as transformations used in computer graphics. The graphics controller card for the Apollo Computer DN570 Workstation, released in 1985, was based on the TMS32010 and could transform 20,000 2D vectors every second.

The TMS320 architecture has been around for a while so a number of product variants have developed. The product codes used by Texas Instruments after the first TMS32010 processor have involved a very popular series of processor named TMS320Cabcd where a is the main series, b the generation and cd is some custom number for a minor sub-variant.

For this reason people working with DSPs often abbreviate a processor as "C5x" when the actual name is something like TMS320C5510, since all products obviously have the name "TMS320" and all processors with "C5" in the name are code compatible and share the same basic features. Sometimes you will even hear people talking about "C55x" and similar subgroupings, since processors in the same series and same generation are even more similar.

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