CAMAC (o IEEE 583)BUZ NORMALIZADO

DEFINICION

El bus CAMAC (Computer Automated Measurement and Control) Se introdujo para interconectar instrumentos de medida nucleares en 1969.

The bus allows data exchange between plug-in modules (up to 24 in a single crate) and a crate controller, which then interfaces to PC or to a VME-CAMAC interface.

The standard was originally defined by the ESONE Committee as standard EUR 4100 in 1972, and covers the mechanical, electrical and logic of a parallel bus (dataway) for the plug-in modules.

Several standards have been defined for multiple crate systems including the Parallel Branch Highway definition and Serial Highway definition. Vendor specific Host/Crate interfaces have also been built.

Within the dataway, modules are addressed by slot (Geographical addressing). The left-most 22 slots are available for application modules while the right-most two slots are dedicated to a crate controller.

Within a slot the standard defines 16 subaddresses (0–15). A slot commanded by the controller with one of 32 function codes (0–31).

Of these function codes, 0–7 are read functions and will transfer data to the controller from the addressed module, while 16–23 are write function codes which will transfer data from the controller to the module.

The original standard was capable of one 24 bit data transfer every microsecond. Later a revision to the standard was released to support short cycles which allow a transfer every 450ns. A follow on upwardly compatible standard Fast CAMAC allows the crate cycle time to be tuned to the capabilities of the modules in each slot.