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OPERATING PROCEDURES
SECURITY FUNCTIONS
I-E96-621A
4 - 5
Execute Mode
This mode applies to the INPCT01 module and is the normal
mode of operation for the PCI. In the execute mode, the host
computer and the INFI 90 Plant Loop interact through the PCI.
PCI firmware and software allows the user to configure the
interface modules through the host computer. Refer to the
Function Code Applications Manual (I-E93-900-20) and the
Enhanced CIU Programmers Reference Manual (I-E93-905-2)
for more information about interface configuration. The PCT
can request exception reports (XRs), collect XRs, exercise con-
trol, allow the operator to adjust tunable module specifica-
tions, configure modules on the Plant Loop and do routine
system security functions.
Error Mode
The PCT enters this mode if the built-in system diagnostics
detect a hardware or execution error. If the PCT detects an
error, the module halts and displays an error code on the CPU
LEDs. Refer to
for corrective action when the PCT
enters the error mode.
SECURITY FUNCTIONS
The PCT performs both hardware and software security checks
to insure module integrity.
Hardware Checks
The PCT does the following hardware checks:
1.
Error Detection and Correction
- Detects single bit and
double bit errors in the dynamic RAM. Corrects single bit
errors; halts PCT operation on double bit errors.
2.
Illegal Address Detection
- Detecting an illegal address
generates a bus error and the PCT halts operation.
3.
Machine Fault Timer
- The microprocessor updates this
timer. A machine fault timeout halts module operation.
Software Checks
The PCT does the following software checks:
1.
Module Diagnostics
- Module diagnostics execute auto-
matically on system power up. PCT faceplate LEDs display
error conditions if the diagnostic tests fail, the PCT status LED
goes red, and the PCT halts.
2.
ROM Checksum Check -
This test verifies checksums of
the UVROM. Discrepancies cause the PCT Status LED to go
solid red and PCT operation halts.