Theory of Operation
TLA721 Benchtop & TLA7XM Expansion Mainframe Service Manual
3- 7
The temperature sense board (A2) monitors the temperatures for each slot within
the chassis. The temperature sense board connects to the backplane through the
ribbon cable at J16.
Expansion Module
Figure 3--3 shows the block diagram for the expansion module when one is
installed in an mainframe and second expansion module is installed in a second
mainframe. You may want to refer to this illustration while reading the following
text.
The primary expansion module, located in the primary benchtop mainframe or
portable mainframe, is connected to the expansion module, located in second
expansion mainframe, by routing signals through three expansion cables. The
expansion module both receives and drives the bus signals in both mainframes.
The expansion modules are connected together by two TTL cables and one ECL
cable.
The MODID register is enabled only when the expansion module is installed in
slot 0 of the expansion mainframe. During power up, the value of the MODID0
signal is sampled. If the signal on MODID0 is low, the expansion module is
determined to be installed in slot 0. If the signal on MODID0 is high, the
expansion module is determined to be installed in slot 1--12.
The SYSCLK (system clock) is buffered and transmitted to the expansion
mainframe from the benchtop mainframe.
The MODID register is enabled only when the expansion module is installed in
slot 0 of the expansion mainframe. During power up, the value of the MODID0
signal is sampled. If the signal on MODID0 is low, the expansion module is
determined to be installed in slot 0. If the signal on MODID0 is high, the
expansion module is determined to be installed in slot 1--12.
The SYSCLK (system clock) is buffered and transmitted to the expansion
mainframe from the benchtop mainframe.
The CLK10 is a differential ECL signal that provides system timing and
reference. The CLK10 is transmitted to the expansion mainframe from the
benchtop mainframe.
On power up, the expansion module determines correct configuration of the
expansion modules and the expansion cables.
Temperature Sense Board
Slot 0 Interface
System Clock
Slot 0 Interface
System Clock
CLK10
Power On Sequence
Summary of Contents for TLA7XM
Page 5: ......
Page 13: ...Table of Contents viii TLA721 Benchtop TLA7XM Expansion Mainframe Service Manual ...
Page 17: ...Service Safety Summary xii TLA721 Benchtop TLA7XM Expansion Mainframe Service Manual ...
Page 21: ...Preface xvi TLA721 Benchtop TLA7XM Expansion Mainframe Service Manual ...
Page 25: ...Introduction xx TLA721 Benchtop TLA7XM Expansion Mainframe Service Manual ...
Page 43: ...Specifications 1 18 TLA721 Benchtop TLA7XM Expansion Mainframe Service Manual ...
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Page 87: ...Adjustment Procedures 5 2 TLA721 Benchtop TLA7XM Expansion Mainframe Service Manual ...
Page 161: ...Repackaging Instructions 6 74 TLA721 Benchtop TLA7XM Expansion Mainframe Service Manual ...
Page 165: ...Electrical Parts List 8 2 TLA721 Benchtop TLA7XM Expansion Mainframe Service Manual ...
Page 169: ...Diagrams 9 4 TLA721 Benchtop TLA7XM Expansion Mainframe Service Manual ...
Page 189: ...Mechanical Parts List 10 20 TLA721 Benchtop TLA7XM Expansion Mainframe Service Manual ...