Automationdirect.com DirectLOGIC DL205 Series User Manual page 358

Gray Code (GRAY)
The Gray code instruction converts a 16-bit gray code value to
230
a BCD value. The BCD conversion requires 10 bits of the
240
accumulator. The upper 22 bits are set to "0". This instruction
250-1
is designed for use with devices (typically encoders) that use
260
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
DS Used
revolution. If a device having a resolution of 360 counts per
HPP Used
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.
DirectSOFT
X1
LDF K16
X10
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
Handheld Programmer Keystrokes
$ B
ENT
STR 1
L D F
SHFT
ANDST 3 5
G R A Y
SHFT
6 ORN 0 MLS
GX V C
SHFT
OUT AND
Chapter 5: Standard RLL Instructions - Number Conversion
31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16
Acc. 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16
Acc. 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
B A B
1 0 1
ENT
A B A
ENT
2 0 1 0
X27
OFF
15 14 13 12 11 10 9
0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 1
15 14 13 12 11 10 9
0 0 0 0 0 0 0 0 0 0 0 0 0 1 1 0
Gray Code
0000000000
0000000001
0000000011
0000000010
0000000110
G
ENT
6
0000000111
0000000101
0000000100
•
•
•
1000000001
1000000000
DL205 User Manual, 4th Edition, Rev. B
GRAY
X26 X25 X12 X11
OFF OFF ON OFF
8 7 6 5 4 3 2
8 7 6 5 4 3 2
BCD
0 0 0 6
0000
0001
V2010
0002
0003
0004
0005
0006
0007
•
•
•
1022
1023
5–141
1
2
3
4
5
6
7
8
X10
ON
9
10
1 0
11
1 0
12
13
14
A
B
C
D