AM16/32B Relay Multiplexer 16
Terminals (SETs). With the mode switch set to 4x16, the blue channel numbers apply. The SETs are
numbered starting at 1 (1H, 1L, 2H, 2L) and continuing until SET 16 (31H, 31L, 32H, 32L).
In 4x16 mode, the odd-numbered terminals (example: 5H, 5L) are relay-switched to the COM
ODD terminals while the even terminals (6H, 6L) are switched to the COM EVEN terminals. When
activated by the RES line, as the AM16/32B receives clock pulses from the data logger, each SET of
four in turn is switched into contact with the four COM terminals. For example, when the first
clock pulse is received from the data logger, SET 1, consisting of 1H, 1L, 2H, and 2L, is connected
to COM ODD H, ODD L, EVEN H, and EVEN L terminals respectively. When the second clock pulse
is received, the first SET is switched out (SET 1 sensor inputs become open circuits), and SET 2 (3H,
3L, 4H, 4L) are connected to the four COM terminals. A given SET will typically be connected to
the common terminals for 10 ms.
With the mode switch set to 2x32, the white channel numbers apply. The SETs are labeled
beginning with 1H, 1L and ending with 32H, 32L. In 2x32 mode when the AM16/32B selects a
given channel, the H terminal is relay-connected to both COM H terminals, and the L sensor
terminal is connected to both COM L terminals.
8.1
Programming
8.1.1
Short Cut
programs
In most cases,
Short Cut is the best way to create or begin data logger programs for the
(p. 3) for a
Short Cut tutorial. The details that follow pertain
to CRBasic programs generated by
Short Cut.
NOTE:
To accommodate the AM16/32 and AM16/32A,
Short Cut adds a delay of 150 ms after enabling
the multiplexer. This delay is not required for the AM16/32B and may be deleted to increase the
speed of the program.
When programming with
Short Cut, three instructions operate the multiplexer: 1) the
PortSet()
instruction enables or disables the multiplexer, 2) the
SubScan()
/
NextSubScan
instruction
begins/ends the measurement loop, and 3) the
PulsePort()
instruction clocks through the
measurement channels. The CRBasic program must also specifically increment an index variable
and use that variable to determine where each measurement is stored. The generalized
programming sequence follows: