NPM PPCI7443, Руководство пользователя

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Operation Theorem
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4.2 The motor driver interface
The PPCI7443 provides the INP, ALM, ERC, SVON, RDY signals for
servomotor driver’s control interface.
The INP and ALM are used for
feedback the servo driver’s status. The ERC is used to reset the servo
driver’s deviation counter under special conditions. The SVON is general-
purposed output signal, and RDY is general-purposed input signal. The
meaning of “general-purposed” is that the processing of signal is not a
build-in procedure of hardware. The hardware processes INP, ALM and
ERC signals according to pre-defined rule. For example, when receiving
ALM signal, the PPCI7443 stop or decelerate to stop output pulses
automatically. However, SVON and RDY are not that case, they actually act
like common I/O.
4.2.1 INP
The processing of INP signal is a hardware build-in procedure, and it is
designed to cooperate with the in-position signal of servomotor driver.
Usually, servomotor driver with pulse train input has a deviation (position
error) counter to detect the deviation between the input pulse command and
feedback counter. The driver controls the motion of servomotor to minimize
the deviation until it becomes 0.
Theoretically, the servomotor operates
with some time delay from command pulses. Accordingly, when the pulse
generator stops outputting pulses, the servomotor does not stop but keep
running until the deviation counter become zero. Then, the servo driver
sends out the in-position signal (INP) to the pulse generator to indicate the
motor stops running.
Usually, the PPCI7443 stops outputting pulses upon completion of
outputting designated pulses.
But by setting parameter inp_enable in
_7443_set_inp() function, you can delay the completion of motion to the
time when the INP signal is turned on, ie, the motor arrives the target
position. Status of _7443_motion_done() and INT signal are also delayed.
That is, when performing under position control mode, the completion of
_7443_start_ta_move(), _7443_start_sr_move(),…etc, is delayed until
INP signal is turned ON.
The in-position function can be enable or disable, and the input logic
polarity is also programmable by parameter “inp_logic” of
_7443_set_inp().
The INP signal status can be monitored by software function:
_7443_get_io_status().
Relative Functions:
_7443_set_inp() : Refer to section 6.12
_7443_get_io_status() : Refer to section 6.13
_7443_motion_done() : Refer to section 6.11