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INTRODUCTION
I-E96-213A
2 - 1
SECTION 2 - DESCRIPTION AND OPERATION
INTRODUCTION
This section explains the functional blocks that make up the
MFC. It also describes data bus communications and security
functions of the hardware.
MODULE DESCRIPTION
The IMMFC05 is a series of functional blocks working together.
To help you understand how the MFC works, this section
shows the MFC as a block diagram and then explains each
block in the following text. See Figure
Microprocessor
The microprocessor, which operates at 12 Megahertz, is
responsible for module operation and control. The processor's
operating system instructions and the function code library
reside in the read only memory (ROM). Since the processor is
responsible for total operation, it communicates with all func-
tional blocks. The processor also does one other critical task. It
constantly re-triggers the Machine Fault Timer (MFT) circuit. If
the processor or software fails and the MFT is not reset, the
MFT issues a board-wide reset and the Status LED turns red.
This condition is known as a fatal error.
Figure 2-1. IMMFC05 Block Diagram
T00021A
DATA BUS
SLAVE
EXPANDER
BUS
TO P2
I/O SECTION
LEDS,
SWITCHES
MASTER
CONTROL
OUTPUT
MODULE
BUS
TO P1
REDUNDANCY
LINK
TO P3
SAC/DCS
LINK
TO P3
BAT-RAM
ROM
RAM
MACHINE
FAULT
TIMER
MICRO-
PROCESSOR
CLOCK/
TIMER