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2.4: Serial number. L-502 version number. Module identification in a multi-module
configuration
Green light
L-502 is in the synchronous I/O mode.
No lights
Power is off.
If more than one L-502 module is used in the computer's system unit, the task is to identify
the module with which the program is currently running. To solve this problem, the software
function of controlling the red glow of the LED is provided. Naturally, the same problem can be
solved by software reading the serial number of the module, however, a comparison with the
number punched on the board will require the opening of the system unit, which is inconvenient for
operation.
2.4. Serial number. L-502 version number. Module
identification in a multi-module configuration
The unique eight-digit product serial number item
instance throughout the life cycle. The L-502 serial number is program-accessible.
The first digit of the serial number corresponds to the version number of the product L-502.
The product version is changed to improve the design and technological characteristics during the
production "life cycle" of the product.
All versions of L-502 are programmed and functionally
identical.
The task of module identification in a multi-module configuration arises because PCI Express
(as well as PCI) -interface historically has never had a software binding to the physical position of
the module in the slot line, and this binding occurs in operating systems when the system is
initialized. If the composition of the equipment has not changed (and all the equipment remains
operative), then there is a hope that the assignment of resources in the system during the
initialization should occur from one computer to another. But in order to reliably compare a
particular instance of the module and its assigned address
in a multi-module user program, it is
necessary to bind to the serial number of the L-502 module.
