Delta Tau 24E2A, Руководство пользователя

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Accessory 24E2A
Flag Capture Control (MSn,MI911-MI913)
The flag capture registers must also be set up at the MACRO Station for proper homing, encoder
capturing, and setting compare outputs.
MI911 determines which encoder input the position compare circuitry for the machine interface channel
mapped to the specified node uses.
MSn,MI911=0
Use channel n encoder counter for position compare function
MSn,MI911=1
Use first encoder counter on IC (encoder 1 for channels 1 to 4; encoder 5 for
channels 5 to 8) for position compare function
When MI911 is set to 0, the channel’s position compare register is tied to the channel’s own encoder
counter, and the position compare signal appears only on the EQUn output.
When MI911 is set to 1, the channel’s position compare register is tied to the first encoder counter on the
ASIC (Encoder 1 for channels 1-4, Encoder 5 for channels 5-8, or Encoder 9 for channels 9-10) and the
position compare signal appears both on EQUn and combined into the EQU output for the first channel
on the IC (EQU1 or EQU5); executed as a logical OR.
MI911 for the first channel on an ASIC performs no effective function, so is always 1. It cannot be set to 0.
MI912 determines which signal or combination of signals, and which polarity, triggers a position capture
of the counter for the encoder mapped to the specified node. If a flag input (home, limit, or user) is used,
MI913 for the node determines which flag. Proper setup of this variable is essential for a successful home
search, which depends on the position-capture function. The following settings may be used:
0: Capture under software control (armed)
1: Capture on Index (CHCn) high
2: Capture on Flag high
3: Capture on (Index high AND Flag high)
4: Capture under software control (latched)
5: Capture on Index (CHCn) low
6: Capture on Flag high
7: Capture on (Index low AND Flag high)
8: Capture under software control (armed)
9: Capture on Index (CHCn) high
10: Capture on Flag low
11: Capture on (Index high AND Flag low)
12: Capture under software control (latched)
13: Capture on Index (CHCn) low
14: Capture on Flag low
15: Capture on (Index low AND Flag low)
The trigger is armed when the position capture register is read. After this, as soon as the Compact
MACRO Station sees that the specified input lines are in the specified states, the trigger will occur — it is
level-trigger, not edge-triggered.
MI913 parameter determines which of the Flag inputs will be used for position capture (if one is used, see
MI912):
0: HMFLn (Home Flag n)
1: PLIMn (Positive End Limit Flag n)
2: MLIMn (Negative End Limit Flag n)
3: USERn (User Flag n)
Typically, this parameter is set to 0 or 3, because in actual use the LIMn flags create other effects that
usually interfere with what is trying to be accomplished by the position capture. To capture on the LIMn
Ultralite/MACRO Station Setup 29