DSP boards or digital signal processor computer boards are central to the implementation of high-performance industrial systems. They collect and process digital data from many sources, and distribute the results to other elements of the system. There are three main sources of data in a real system: signals (in and out from the DSP processor), messages to communicate with system controllers, and messages to communicate with other DSP boards. Important features of DSP boards include a fast processor and good communication channels as DSP boards need to collect and distribute data from/to many different sources.
Computer backplane or bus choices for DSP boards include PCI, ISA or EISA, PCMCIA, PC/104, Mac PCI, SUN Sbus, PMC bus, PXI bus, Multibus, STD bus, VME bus, VXI or MXI bus, and DT-connect I and II interface. PCI is a local bus system designed for high-end computer systems. ISA is a standard for I/O buses that was set back in 1984 when IBM was the standard. PCMCIA devices (PC Cards) are credit-card-sized peripherals predominantly used in laptop computers. PC/104 gets its name from the desktop personal computers designed by IBM (PCs), and from the number of pins used to connect the cards together (104). Mac PCI is a local bus standard developed by the Intel Corporation. Designed by Sun in 1989, the SBus board was the standard I/O inter-connect for Sun computers, which typically run under the Solaris or SunOS flavor of the UNIX operating system. The PMC Bus is actually a form factor, not a bus -- it is electrically the same as the PCI Bus, but the shape of the card and the bus connectors are different. PXI is a superset of CompactPCI and adds timing and triggering functions, imposes requirements for documenting environmental tests, and establishes a standard Windows-based software framework. STD bus is often referred to as the "Blue Collar Bus" because of its rugged design and small size, the STD Bus was originally designed for factory and industrial environments. It uses 16-bit architecture. VME bus is a 32-bit bus used in industrial, commercial and military applications. Motorola developed the VME standard, with others, in the late 1970s. DT-connect I and II is Data Translation's DT-Connect Interface.
Important processor or DSP performance specifications to consider for DSP boards include number of processors, clock speed, floating point performance, integer performance, operations, maximum addressable memory, and operating temperature. General features and options to consider when looking for DSP boards include real-time clock, interrupt controller, memory management unit, dual port memory, and direct memory access. Communications options include serial I/O ports, parallel I/O ports, on board A/D converter, and on board D/A converter. Some DSP boards can accept daughter boards and some DSP boards are daughter boards. An important environmental parameter to consider when searching for DSP boards is the operating temperature.