AutomationDirect DL205 - Channel Update Sequence for DL240, DL250-1, and DL260 Cpus (Pointer Method)

DL205 Analog Manual, 7th Edition Rev. D
11-9
Chapter 11: F2-08DA-2, 8-Channel Analog Voltage Output
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Channel Update Sequence for DL240, DL250-1, and DL260 CPUs
(Pointer Method)
If either a DL240, DL250-1 or a DL260 CPU is used with the pointer method, all channels
can be updated on every scan. This is because the three CPUs support special V-memory
locations that are used to manage the data transfer. This is discussed in more detail in the
next section on Writing the Control Program.
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Channel 1, 2...8
Channel1,2...8
Channel1,2...8
Channel1,2...8
Scan N
Calculatethe data
Writedata
Read inputs
ExecuteApplicationProgram
Scan N+1
Scan N+2
Scan N+3
Scan N+4
Scan
Writeto outputs
System With
DL240/250-- 1/260
CPUUsing
Pointer Method
Channel 1, 2...8