Delta MMC120 - Manual (Page 122)

122
OFFSET + 65535.
Example 3:
SCALE : 32050
OFFSET : 1000
Position Range: 1000 to 65535
Discussion: Because
SCALE is positive, the positions range from OFFSET to
OFFSET + 65535. However, because the upper limit would be greater than 65535
(66535), it is truncated at 65535.
Example 4:
SCALE : -30300
OFFSET : 40000
Position Range: -25535 to 40000
Discussion: Because
SCALE is negative, the positions range from OFFSET - 65535
to OFFSET .
Example 5:
SCALE : -31541
OFFSET : -10000
Position Range: -65536 to -10000
Discussion: Because
SCALE is negative, the positions range from OFFSET - 65535
to OFFSET . However, because the lower limit would be less than -65536 (-75536),
it is truncated at -65536.
COMMAND POSITION
The COMMAND POSITION is the requested position (specified by the COMMAND
VALUE ) with bounds checking applied. If the requested position is outside the
RETRACT or EXTEND LIMIT , the COMMAND POSITION will be set to the value of
the limit, and the axis will go only to the limit. The COMMAND POSITION is updated
when any move command, or 'P' command is issued using the COMMAND parameter.
Why Bother?
If the COMMAND POSITION is not the same as the requested position then one of two
things has happened:
1. A program error has asked the axis to go to an invalid position. In this case the
program error should be corrected. The PARAMETER ERROR bit in will be ON
when this occurs.
2. The COMMAND VALUE field has just been changed and the Motion Controller
has not had a chance to acknowledge the new request. Note that the IN POSITION
bit is no longer valid for the rest of the scan. The IN POSITION bit is valid only
when the COMMAND VALUE is equal to the COMMAND POSITION.