If more channels are requested than exist in one module, the datalogger automatically increments the address and continues to the next SW8A. The address settings for multiple SW8A's must sequentially increase. For example, assume 2 SW8A's with an address of 22 and 23 are connected, and 12 Reps are requested. Eight channels from the first SW8A and the first 4 channels from the second SW8A will be read.

Only one Function Option (Parameter 3) may be specified per P102 Instruction. If all 4 functions are desired, 4 P102 Instructions are required.

Function Option 0 provides the state of the signal at the time P102 is executed. A 1 or 0 corresponds to high or low states, respectively.

Function Option 1 provides signal duty cycle. The result is the percentage of time the signal is high during the sample interval.

Function Option 2 provides a count of the number of positive transitions of the signal.

Function Option 3 provides the signature of the SW8A PROM. A positive number (signature) indicates the PROM and RAM are good, a zero

(0)indicates bad PROM, and a negative number indicates bad RAM. Function Option 3 is not used routinely, but is helpful in "debugging". Only one Rep is required for Option 3.

Parameter 4 specifies the first SW8A channel to be read (1..8). One or more sequential channels are read depending on the Reps. To optimize program efficiency, the sensors should be wired sequentially.

Data are stored in sequential input locations, starting at the location specified in Parameter 5. The number of input locations consumed is equal to the number of Reps.

The scaling multiplier and offset (Parameters 6 and 7) are applied to all readings. If a multiplier is not entered, all readings are set to 0.

If the SW8A does not respond, -99999 will be loaded into input locations. Modules which do not respond when addressed by the datalogger are possibly wired or addressed incorrectly.

Verify the address specified in Parameter 2 corresponds to the jumper setting and all connections are correct and secure. See the SDM-SW8 Manual for examples.

SECTION 9. INPUT/OUTPUT INSTRUCTIONS

PARAM.

DATA

 

NUMBER

TYPE

DESCRIPTION

01:

2

Number of Channels

02:

2

Module Address (00..33)

03:

2

Function Option

 

 

(0=State, 1=Duty,

 

 

2=Counts, 3=Signature)

04:

2

SDM-SW8A Starting

 

 

Channel (1..8)

05:

4

Starting input location

06:

FP

Mult

07:

FP

Offset

*** 103 SDM-AO4 ***

FUNCTION

Instruction 103 is used to activate a SDM-AO4 connected to ports C1, C2, and C3.

There are 4 analog voltage outputs per SDM- AO4. The output voltages in millivolts must be stored in 4 adjacent input locations starting with the location entered in parameter 3. Four reps are required for each SDM-A04. Every 4 reps another device at the next higher address is selected.

PARAM.

DATA

 

NUMBER

TYPE

DESCRIPTION

01

2

Reps (# of outputs)

02

2

Address (Base 4)

03

4

Starting input location

C1 is Data line

C2 is Clk/Hand Shake line

C3 is SDE (Enable) line

*** 104 SDM-CD16AC ***

FUNCTION

The SDM-CD16AC Control Port Expansion Module has 16 digital control ports with drivers. Each port can be controlled by a datalogger or controlled manually with an override toggle switch. Each port can be thought of as a switch to ground; closed when active, open when inactive. The primary function is to activate AC powered external relays, solenoids, or resistive loads under datalogger control.

The SDM-CD16AC is a synchronously addressed datalogger peripheral. Datalogger control ports 1, 2 and 3 are used to address the SDM-CD16AC then clock out the desired state

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