Section 5. Programming the Datalogger

see ‘SDM Port’ in Section 1 for details. This should be connected to control port

8 for this example.

A typical filter that could be used is as follows:

fltst 200 "t[data]A5xff"

This filter works as follows:

t[data] – this filter waits for an exact string match before it starts the next filter. In this case it is waiting for the sensor to send the string ‘data’.

A5 – this filter sets up a 250ms filter time out. This time out should be long enough for the sensor to transmit all of its data.

x – this filter marks the start of the data set. In this case the data set is two floating point numbers.

f – this filter searches for the first ASCII floating point number to convert.

f – this filter searches for the second ASCII floating point number to convert.

*Table 1 Program

01: 2 Execution Interval (seconds)

;set control port 8 to i/p so it can be used as an interrupt

1:Set Port(s) (P20)

1:8999 C8..C5 = input/nc/nc/nc

2:9999 C4..C1 = nc/nc/nc/nc

;do filter setup only if flag one is clear

2:If Flag/Port (P91)

1:21 Do if Flag 1 is Low

2: 30

Then Do

;set up string filter

3:SDM-SIO4 (P113)

1: 1

Reps

2: 0

Address

3: 1

Send/Receive Port 1

4: 2054

Command

5: 9200

1st Parameters

6: 0

2nd Parameters

7: 0

Values per Rep

8:0 Loc [ _________ ]

9:1.0 Mult

10:0.0 Offset

;delay required by filter setup command

4:Excitation with Delay (P22)

1:1 Ex Channel

2:0 Delay W/Ex (units = 0.01 sec)

3:1 Delay After Ex (units = 0.01 sec)

4:0 mV Excitation

;set flag one high so the filter set-up is only done once

5:Do (P86)

1:11 Set Flag 1 High

5-23

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Image 53
Campbell Hausfeld SDM-SIO4 manual Set control port 8 to i/p so it can be used as an interrupt