Delta Tau GEO BRICK LV User Manual
Turbo PMAC User Manual
358
Synchronizing Turbo PMAC to External Events
By having software setup for a hardware capture, Turbo PMAC gets the best of both worlds: the
flexibility of software configuration, plus the immediacy and accuracy of hardware capture. It is possible
to have one setup for homing and another for probing or registration, for example, both with the high
accuracy of hardware capture, and the change requires no rewiring.
flexibility of software configuration, plus the immediacy and accuracy of hardware capture. It is possible
to have one setup for homing and another for probing or registration, for example, both with the high
accuracy of hardware capture, and the change requires no rewiring.
Automatic Move-Until-Trigger Functions
Turbo PMAC has three types of move-until-trigger functions that can use the hardware position-capture
feature to latch the triggered position:
1. Homing search moves (on-line or in a motion program)
2. On-line jog-until-trigger moves
3. Motion
feature to latch the triggered position:
1. Homing search moves (on-line or in a motion program)
2. On-line jog-until-trigger moves
3. Motion
program
RAPID-mode
moves-until-trigger
All of these create basically the same type of motion. All of them end their post-trigger move at a pre-
defined distance from the triggered position. These moves are described in detail in the Executing
Individual Motor Moves section of this manual.
defined distance from the triggered position. These moves are described in detail in the Executing
Individual Motor Moves section of this manual.
Manual Use of the Capture Feature
If the automatic move-until-trigger functions do not accomplish the action needed, create custom
functions by accessing the capture registers directly.
functions by accessing the capture registers directly.
Position-Capture Registers and Flags
Each channel in a Turbo PMAC Servo IC has position-capture registers and a position-capture flag.
Position-Capture Flag
Each channel has a position-capture flag in the channel’s status word. In PMAC-style Servo ICs, this is
bit 17; in PMAC2-style Servo ICs, this is bit 11. This bit is set to 1 by the IC’s capture logic when the
trigger condition occurs and the position is latched into the capture register(s). It is set to 0 when the
(whole count) capture-position register is read by the processor. The act of reading this register
automatically resets and re-arms the capture logic.
Each channel has a position-capture flag in the channel’s status word. In PMAC-style Servo ICs, this is
bit 17; in PMAC2-style Servo ICs, this is bit 11. This bit is set to 1 by the IC’s capture logic when the
trigger condition occurs and the position is latched into the capture register(s). It is set to 0 when the
(whole count) capture-position register is read by the processor. The act of reading this register
automatically resets and re-arms the capture logic.
Note:
The capture circuits in PMAC-style Servo ICs are edge-triggered. After the
capture logic is reset by reading the position-capture register, the triggering
input(s) must create another edge to the capturing state before the next capture will
occur. By contrast, the capture circuits in PMAC2-style Servo ICs are level-
triggered. If the triggering input(s) is (are) still in the capturing state when the
capture logic is reset, another capture will occur immediately.
capture logic is reset by reading the position-capture register, the triggering
input(s) must create another edge to the capturing state before the next capture will
occur. By contrast, the capture circuits in PMAC2-style Servo ICs are level-
triggered. If the triggering input(s) is (are) still in the capturing state when the
capture logic is reset, another capture will occur immediately.
For PMAC-style Servo ICs, the M-variable definitions for the position-capture flags are shown in the
following table. With the standard assignment of channels to motors, the suggested M-variable for the
flag for Motor xx is Mxx17.
following table. With the standard assignment of channels to motors, the suggested M-variable for the
flag for Motor xx is Mxx17.
Servo IC #
Channel 1
Channel 2
Channel 3
Channel 4
0 X:$078000,17 X:$078004,17 X:$078008,17 X:$07800C,17
1 X:$078100,17 X:$078104,17 X:$078108,17 X:$07810C,17
2 X:$078200,17 X:$078204,17 X:$078208,17 X:$07820C,17
3 X:$078300,17 X:$078304,17 X:$078308,17 X:$07830C,17
4 X:$079000,17 X:$079004,17 X:$079008,17 X:$07900C,17
5 X:$079100,17 X:$079104,17 X:$079108,17 X:$07910C,17
6
1 X:$078100,17 X:$078104,17 X:$078108,17 X:$07810C,17
2 X:$078200,17 X:$078204,17 X:$078208,17 X:$07820C,17
3 X:$078300,17 X:$078304,17 X:$078308,17 X:$07830C,17
4 X:$079000,17 X:$079004,17 X:$079008,17 X:$07900C,17
5 X:$079100,17 X:$079104,17 X:$079108,17 X:$07910C,17
6
X:$07A200,17 X:$07A204,17 X:$07A208,17 X:$07A20C,17
7
X:$07A300,17 X:$07A304,17 X:$07A308,17 X:$07A30C,17
8 X:$07B200,17 X:$07B204,17 X:$07B208,17 X:$07B20C,17
9 X:$07B300,17 X:$07B304,17 X:$07B308,17 X:$07B30C,17
9 X:$07B300,17 X:$07B304,17 X:$07B308,17 X:$07B30C,17