Red Lion GEMINI 2 - Manual (Page 18)

PROGRAMMING INSTRUCTIONS FOR THE RATE INDICATOR VERSION OF THE GEMINI
The first part of this section provides detailed descriptions of the function
command codes for scale multiplier, leading zero blanking, output terminations,
etc. Then, using an actual application example, the programming instructions for
a rate indicator will be “walked through” to give the user a full understanding of
the Gemini programming procedure. The descriptions below give the Function
Command Code first, followed by the individual mode identifier. The Function
Command Code Summary in Appendix “D”, lists all codes. (Only commands
and modes pertaining to the rate indicator will be discussed in this section).
CODE 41 - UNIT PERSONALITY
Two basic personalities are available for the Gemini. They are the counter
mode and the rate indicator mode.
[41 2] RATE INDICATOR - Setting this mode selects the unit to function as a
rate indicator. This is the basic personality mode and must be programmed
before any other modes are set. (This command forces default mode values in
certain command codes.)
CODE 44 - NUMBER OF COUNT EDGES
The Gemini can be programmed for either single edge or two edge (doubling)
counting.
[44 1] SINGLE EDGE COUNTING - The unit counts on the negative going
(falling) edge of the count input signal.
[44 2] TWO EDGE COUNTING - This mode is used when doubling of the count
signal input is required. The unit counts on the positive going (rising) edge of
the count input signal, as well as, the negative going (falling) edge. This
effectively doubles the resolution of the input signal.
CODE 45 - SCALE MULTIPLIER
There are four scale multiplier values that are available. They are: 1; 0.1; 0.01;
and 0.001. They effectively divide the internal count value by 1, 10, 100, and
1000 respectively, to yield the displayed rate value.
[45 1] SCALE MULTIPLIER VALUE OF 1 - This value multiplies the internal
rate by 1.
[45 2] SCALE MULTIPLIER VALUE OF 0.1 - This value multiplies the
internal rate by 0.1. (Effectively divides by 10.)
[45 3] SCALE MULTIPLIER VALUE OF 0.01 - This value multiplies the
internal rate by 0.01. (Effectively divides by 100.)
[45 4] SCALE MULTIPLIER VALUE OF 0.001 - This value multiplies the
internal rate by 0.001. (Effectively divides by 1000.)
CODE 46 - DECIMAL POINT & LEADING ZERO BLANKING
There are six basic modes of decimal point placement on the Gemini. The
decimal point is placed to the right of the display digit that corresponds to the
mode identifier. (The right most decimal point, digit 1, is never turned on.) A “-”
sign in front of the mode identifier will inhibit leading zero blanking. The
absence of the “-” sign will enable leading zero blanking.
[46 1]
0
[46 2] 0.0
[46 3] 0.0 0 LEADING ZERO
[46 4] 0.0 0 0 BLANKING
[46 5] 0.0 0 0 0
[46 6] 0.0 0 0 0 0
[46 -1] 0 0 0 0 0 0
[46 -2] 0 0 0 0 0.0
[46 -3] 0 0 0 0.0 0 LEADING ZERO
[46 -4] 0 0 0.0 0 0 BLANKING INHIBITED
[46 -5] 0 0.0 0 0 0
[46 -6] 0.0 0 0 0 0
CODE 51 - RESET MODES (Manual Reset to Zero)
In the majority of rate indicator applications, the setting of function code 51 is
not relevant to the desired operation of the unit, and thus need not be
programmed. The Gemini is designed to automatically update at the end of every
sample time cycle, which will provide a continuous rate indication reading, as is
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