Instruction manual

45
Appendix A – use of an AM25T multiplexer:
Listing of logger programme to connect 3 heat-pulse units to a single CR10 data logger.
Note: One AM25T could be used to measure up to 6 heat-pulse units, but this requires a
small modification to the programme described below. Please email the author for details.
CR10: AM25T
+12 +12
G G
C3 CLK
C2 RES
no connection EX
AG AG
1H HI
1L LO
(1H, 1L, 2H, 2L) Output from box-1, probe 1
(3H, 3L, 4H, 4L) Output from box-1, probe 2
(5H, 5L, 6H, 6L) Output from box-2, probe 1
(7H, 7L, 8H, 8L) Output from box-2, probe 2
and so on ...
*Table 1 Program
01: 0.25 Execution Interval (seconds)
1: If time is (P92) ;
Flag 1
is automatic sampling
1: 0000 Minutes (Seconds --) into a ; once every 30 minutes
2: 30 Interval (same units as above)
;Change as required
3: 11 Set Flag 1 High
2: If Flag/Port (P91) ;
Flag 5
is set when
t
z
is calculated
1: 15 Do if Flag 5 is High
2: 30 Then Do
3: Timer (P26)
1: 99 Loc [ _________ ]
4: Do (P86) ; Activate AM25T
1: 42 Set Port 2 High ;
Connect
Port 2
(C2) to Reset on AM25T
5: Beginning of Loop (P87) ; Measure inputs on 2*N boxes
1: 0000 Delay
2: 12 Loop Count ; (2* N boxes) Change as required
6: Step Loop Index (P90)
1: 2 Step
7: Do (P86) ; Connect
Port 3
(C3) to Clock on AM25T
1: 43 Set Port 3 High
8: Do (P86)
1: 53 Set Port 3 Low
9: Do (P86)
1: 43 Set Port 3 High
10: Do (P86)