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TM 11-6625-3145-14
Theory of Operation-318/338 Service
The signals TRIG A, TRIG B, TRIG C, EXTVG FLAG, and TRIG QUAL are latched into each flip-flop by the retiming clock.
TRIG A, TRIG B, and TRIG C are issued by the word recognizers on the A01 and the A02 boards.
The outputs of these flip-flops are wire-ORed with the outputs of the address buffer (A03U140 and A03U154B and
A03U154C) and go to the address inputs of the SQRAM.
ADDRESS BUFFER <7>
The address buffer consists of A03U140, A03U154B, and A03U154C. These gates can be enabled only while setting up
the SQRAM.
Their outputs are used as the address to the SQRAM when loading the trigger sequencer table.
The control signal for the gates is called LDSQRAM. LDSQRAM comes from A03U108 <5>.
TRIGGER SEQUENCER RAM <7>
The trigger sequencer RAM (SQRAM) is a 4-bit high-speed memory, consisting of A03U144.
This memory can be operated in either read or write mode. Before acquisition, the memory is operated in write mode.
During acquisition, the SQRAM is operated in the Read mode.
To provide a trigger sequencer table to the SQRAM, the MPU writes the data already set in the data register (A03U106
and A03U108 <5>) into the SQRAM at I/O address 58
hex
. The address to the SQRAM is supplied by the MPU data.
The memory address is determined by the current status of the retiming flip-flops. The data from SQRAM is applied to the
trigger sequencer circuit.
The data consists of four signals: CE., LOADN, LOADDN, and SUCCEED.
The CE signal enables the event/delay counter in the LSI-A.
The LOADN signal indicates that the contents of the N register in LSI-A is loaded into the event/ delay counter at the rising
edge of the trigger clock.
The LOADDL signal indicates that the contents of the DL register in LSI-A are loaded into the event/delay counter by the
trigger clock, and at the same time, the delay sequence begins.
The SUCCEED signal is used when the trigger sequence is in the succeed mode. The trigger words must be satisfied
sequentially in order to generate the trigger.
TRIGGER SEQUENCER FLAG <7>
The trigger sequencer flag circuit consists of A03U122C, A03U148A, A03U148B, A03U150A, A03U150B, A03U152A,
A03U152B, A03U154A, A03U154D, A03U156A, A03U156B, A03U156C, and A03U156D.
It contains four main flags: N flag, TRIG’D flag, SUCCEED flag, and STOP flag.
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Summary of Contents for 318
Page 119: ...318 VERIFICATION AND ADJUSTMENT PROCEDURES ...
Page 182: ...338 VERIFICATION AND ADJUSTMENT PROCEDURES ...
Page 253: ...318 ___________________ TROUBLESHOOTING TREES ...
Page 344: ...338 TROUBLESHOOTING TREES ...
Page 517: ...TM 11 6625 3145 14 318 338 4434 923 318 Block Diagram ...
Page 518: ...TM 11 6625 3145 14 318 338 4434 924 338 Block Diagram ...
Page 519: ...TM 11 6625 3145 14 318 338 4434 925 318 Acquisition Module Wiring Diagram ...
Page 520: ...TM 11 6625 3145 14 318 338 4434 926 318 338 Mainframe Wiring Diagram ...
Page 521: ...TM 11 6625 3145 14 318 338 4434 926 338 Acquisition Module Wiring Diagram ...
Page 522: ...TM 11 6625 3145 14 318 338 4434 928 Figure 9 1 318 A01 Input A Board Component Locations ...
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Page 528: ...TM 11 6625 3145 14 Figure 9 3 318 338 A03 ACQ Control Board Component Locations ...
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Page 542: ...TM 11 6625 3145 14 Figure 9 8 318 338 A10 CRT Board Component Locations ...
Page 544: ...TM 11 6625 3145 14 Figure 9 9 318 338 A11 Inverter Board component Locations ...
Page 546: ...TM 11 6625 3145 14 Figure 9 10 318 338 A12 Regulator Board Component Locations ...
Page 551: ...TM 11 6625 3145 14 Figure 9 12 338 A01 Input A Board Component Locations ...
Page 553: ...TM 11 6625 3145 14 318 338 SERVICE ...
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