DL205 User Manual, 4th Edition, Rev. D
5-141
Chapter 5: Standard RLL Instructions
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3
4
5
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8
9
10
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A
B
C
D
Gray Code (GRAY)
The Gray code instruction converts a 16-bit gray code value
to a BCD value. The BCD conversion requires 10 bits of the
accumulator. The upper 22 bits are set to “0.” This instruction
is designed for use with devices (typically encoders) that use
the grey code numbering scheme. The Gray Code instruction
will directly convert a gray code number to a BCD number
for devices having a resolution of 512 or 1024 counts per
revolution. If a device having a resolution of 360 counts per
revolution is to be used, you must subtract a BCD value of 76
from the converted value to obtain the proper result. For a
device having a resolution of 720 counts per revolution, you
must subtract a BCD value of 152.
In the following example, when X1 is ON the binary value represented by X10–X27 is loaded
into the accumulator using the Load Formatted instruction. The gray code value in the
accumulator is converted to BCD using the Gray Code instruction. The value in the lower 16
bits of the accumulator is copied to V2010.
GRAY
230
240
250-1
260
Handheld Programmer Keystrokes
DirectSOFT
LDF K16
X10
X1
Load the value represented
by X10–X27 into the lower
16 bits of the accumulator
GRAY
Convert the 16 bit grey code
value in the accumulator to a
BCD value
OUT
V2010
Copy the value in the lower
16 bits of the accumulator to
V2010
0000000000
Gray Code BCD
0000000001
0000000011
0000000010
0000000110
0000000111
0000000101
0000000100
1000000001
1000000000
0000
0001
0002
0003
0004
0005
0006
0007
1022
1023
X10X11X12
ONOFFON