48
3–5
DM Area Data Format
Data is allocated either by bit or by word, though it is often input and output
by decimal digit, i.e., four bits (BCD). Position data is held in two adjacent
words, generally with a direction digit, in the following format.
direction
10
3
10
2
10
1
10
0
10
4
10
5
10
6
0
1
CW
CCW
Second word
First word
Note that the rightmost word is always the first word. If the two words were
m+8 and m+9, for example, the rightmost word would be m+8 and the left-
most would be m+9. Furthermore, the rightmost digit in each word begins in
the lowest bits. Thus, the digits x10
4
and x10
0
above would be held in bits 00
through 03 of their respective words. The direction digit also provides other
information when required.
Only one word is used to store speeds, acceleration time, and deceleration
time. The formats for these are as follows:
Speeds
10
3
10
2
10
1
10
0
Acceleration and Deceleration
10
2
10
1
10
0
Although decimal notation is generally used for data in this manual, data is
handled in the system as binary-coded decimal (BCD) unless otherwise
noted. Note that this data is generally input as decimal, whereas hexadeci-
mal data is input as hexadecimal. The number of digits given for certain data
refers to the decimal digits. For example, “7 digits with direction” indicates
that the first word and rightmost 12 bits of the second word are allocated to
the 7-digit decimal value; the leftmost four bits are allocated to the direction
digit.
3–6
Flags and Other Input Data
IR words n+5 to n+9 are allocated to flags and other inputs that supply infor-
mation about positioning system operation. Although some of these are de-
scribed under specific operations or commands, they are presented together
in
Appendix D for convenience. Of these, an output code has been provided
for user application and four signals, the last four in the list, have been pro-
vided for system debugging.
3–7
DM Area Allocation
The following table can serve as a general coding sheet for the DM area. For
a more detailed table describing the functions of all of the bits in the DM
area, see
Appendix C.
Speeds, Acceleration, and
Deceleration
Data Coding
Coding Sheet
DM Area Allocation
