User manual

110 Register-Based Programming Appendix B
Example: Using a
Multimeter with a
Multiplexer
The flowchart in Figure B-4 shows a typical timing sequence between
closing a multiplexer’s channel and triggering a multimeter. The registers
used are:

- Multiplexer Status Register (base + 04
16
)
- Multimeter Status Register (base + 04
16
)
- Multimeter Command Register (base + 08
16
)
The multiplexer’s Status Register bit 7 is monitored to determine when a
channel can be closed (or opened) and when a channel has finished closing
(or opening). The ultimeter’s Status bit 0 is monitored to determine when a
trigger opcode can be written to the Command Register (the flowchart
assumes the multimeter is already configured).
Figure B-4. Program Timing Between Multiplexer and Multimeter
START
STOP
0
1
0
1
Check
Multiplexer
Status Register
Bit 7
(Busy)
Close
Multiplexer
Channel
(Busy)
Bit 7
Status Register
Multiplexer
Check
Check
Status Register
Bit 5
(MM Comp)
1
0
Wait for
Measurement(s)
to Complete
Have
all
channels been
measured?
B
B
Retrieve Readings
From Voltmeter Data Buffer
no
yes
Check
Status Register
Bit 0
(Cmd/Parm
Command Register
Upcode to
Write Trigger
0
Ready)
A
A