Omron SYSMAC CJ - REFERENCE MANUAL 08-2008 Reference Manual page 542

Conversion Instructions
Description
C: #0011
R Digit 3 Digit 2 Digit 1
C: #0032
R
Digit 3 Digit 2 Digit 1
502
DMPX(077) can perform 16-to-4 bit or 256-to-8 bit conversions. Set the left-
most digit of C to 0 to specify 16-to-4 bit conversion and set it to 1 to specify
256-to-8 bit conversion.
16-to-4 bit Conversion
When the fourth (leftmost) digit of C is 0, DMPX(077) finds the locations of the
leftmost or rightmost ON bits in up to 4 source words and writes these loca-
tions to R beginning with the specified digit. (Set the third digit of C to 0 to find
the leftmost ON bits or 1 to find the rightmost ON bits.)
16-to-4 bit decoding
(Location of leftmost bit (m)
is written to R.)
When two or more digits are being converted, DMPX(077) will write the values
to the digits in R from right to left and will wrap around to the rightmost digit
after the leftmost digit, if necessary.
The following diagram shows some example values for C and the 16-to-4 bit
conversions that they produce.
C: #0030
Digit 0
R Digit 3 Digit 2
Digit 0
C
FInds leftmost bit
(Highest bit address)
m
Leftmost bit
n=2 (Start with digit 2.)
R
R
Digit 1 Digit 0
Section 3-12
l=1 (Convert
2 words.)
C: #0013
Digit 3 Digit 2 Digit 1 Digit 0