Bailey Infi 90 IMSPM01, Instruction, Page: 22 / 52

DESCRIPTION AND OPERATION
2 - 6 I-E96-217A
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MODULE BUS DATA
An SPM receives and interprets commands from a computer.
From these commands, it generates and sends command mes-
sages to an INFI 90 module. Programs permanently stored in
ROM are run to accomplish SPM functions. Execution of a
specified program generates the module address and instruc-
tion code (i.e., command code) an INFI 90 module requires to
accomplish the computer directed function. Table
2-1 is a list
of functions that can be performed using the SPM.
The SPM resident functions are a subset of the INFI-NET to
Computer Interface (INICI01) and Plantloop to Computer Inter-
face (INPCI01/02) unit functions. Refer to the Enhanced Com-
puter Interface Unit Programmer's Reference Manual
I-E93-905-9 for an explanation of these functions and their
use.
The SPM generates a module bus message and directs this
message to a module on the module bus. The message con-
tains:
•
Destination address (0 to 31).
•
Source module address (SPM address).
•
Message code (function to perform).
•
Data (dependent on the type of command).
•
Checksum (generated by module bus interface function).
Table 2-1. SPM Resident Functions
Command Function
SPM RESTART Reset.
DEMAND MODULE
STATUS Read the status of any module in the PCU.
READ PROBLEM
REPORT Read a module problem report of any module.
READ BLOCK OUTPUT Access the output of any function block.
MODULE OPERATION Change a module operating mode.
READ BLOCK Read a function block in any module.
READ NEXT BLOCK Read the next defined function block.
READ DEFAULT BLOCK Read the function block default parameters.
WRITE BLOCK Configure a block in a PCU.
TUNE BLOCK Change the tuning parameters in a block.
DELETE BLOCK Remove a block from a module.