High-Speed Position Capture Function (Capture) - Delta ASDA-B3 Series User Manual

Motion Control

7.2.2 High-speed position capture function (Capture)

The high-speed position capture function (Capture), abbreviated as CAP, uses the external
signal to trigger the high-speed digital input DI3 (-F, -M, B3A-P models) or DI7 (-L models) (with
7
execution time of only 5 µs) to capture the position data of the motion axis and store it in the
data array for further motion control. As the Capture function is executed by the hardware, there
is no lag in the software, and it is able to capture the motion axis' position accurately. While the
Capture function is enabled, the servo drive defines the function of DI3 or DI7 (based on the
models) as data capturing, which means the DI is not user-defined.
The flowchart for high-speed position capturing is shown in Figure 7.2.2.1. You can set the
Capture function in ASDA-Soft, as shown in Figure 7.2.2.2. The relevant parameters are defined
as follows.
P5.036 sets the start address of the data array for storing the captured data; if it is not set, the
default start address is #0. P5.038 sets the number of capturing times, which has to be greater
than 0, otherwise the Capture function is not executed. P1.019.X enables the cycle mode.
When the last data is captured, the number of capturing times is reset to 0 (P5.038 = 0), and the
next cycle starts automatically to capture the previously set number of capturing times.
However, the start address for storing the captured position data is still determined by P5.036;
that is, the captured data in the previous cycle is overwritten by the data captured in the next
cycle. When the Capture function is set to capture multiple points (P5.038 > 1), use P1.020 to
set the masking range for capturing. This prevents the same position data from being captured
repeatedly by setting the masked area within which only one capturing is allowed. P5.039
enables or disables the Capture function and other settings. See the following table for more
information.
P5.039
X
Y
Z
U
7-62
Bit Function
0 Activate Capture
1 Reset position
2 Reserved
3 Execute PR
- Axis source of Capture
- Trigger logic
Minimum interval
-
between each trigger
Description
1: when P5.038 > 0, the capturing starts and DO.CAP_OK
(0x16) is off. Each time one data is captured, the value of
P5.038 is decremented by 1.When P5.038 = 0, it means
the capturing is finished, DO.CAP_OK (0x16) is on, and
Bit 0 is reset to 0. If Bit 0 is already 1, the written value
must not be 1; you can only write 0 to deactivate the
Capture function.
1: after capturing the first data, reset the position of the first
data to the value of P5.076.
-
1: execute PR#50 automatically after all data are captured.
0: the Capture function is disabled
1: reserved
2: CN1 (pulse command)
3: CN2 (motor encoder)
0: NO (normally open)
1: NC (normally closed)
0 - F: 0 - 15 ms
ASDA-B3