Program Control Flow Diagrams - HP 5340A Operating And Service Manual

Model 5340A
Maintenance and Service

5-16. PROGRAM CONTROL FLOW DIAGRAMS

5-17. Figures 5-3 and 5-4 are flow diagrams showing the sequence of actions required in making
Figure 5-3 is a simplified version of Figure 5-4.
a measurement.
theory explains how decisions are made in the flow diagram. See Paragraph 4-236.
5-18. Figure 5-4 lists three sets of numbers: the program address, the selected test number,
and selected action number.
5-19. The program address is the 5-bit binary number placed to the right of the rectangle and
diamond symbols in the diagram. These 5 bits are the inputs to
HP 10528A Logic Clip is installed on A21U4, the program address appears on pins 10
a n
through 14. Note that the logic clip diagram shown on Figure 5-4 uses circles to designate these
pins.
5-20. Inside each rectangle is a decimal number that indicates what action is required and this
corresponds to the action of A21U13. This number can be read in binary on pins 5, 6, 7, and 9
of A21U4. These pins have binary weights 1, 2, 4, and 8, respectively.
action, add the binary weights of the pins activated.
5-21. For example, if A21U4 pins 5, 6, and 7 were
quired action is (1 2 + 4) = 7. Note that the four pins designating action data are diagrammed
+
a s rectangles in the logic clip diagram to correspond with the rectangles of the flow diagram.
5-22. Decision points are indicated by diamonds and the associated decimal number indicates
the test required. This number, which corresponds to the number in A21U12, can similarly be
read on the logic clip on the pins designated with diamonds in the diagram. Note that this cor-
responds to the diamond shapes on the flow chart.
5-23. It may be possible to single step the 5340A through the flow diagram to check for proper
branching. Refer to A21 Troubleshooting.
5-14
The A21 Control Board
To
determine the required
LED),
High (indicated by a lit the re-
I