Command Pulse Counting - Fuji Electric micrex-sx SPH User Manual

7-3 Functions of Pulse Generation Mode

7-3-18 Command pulse counting

• Command pulse counter is counted up/down according to the type of command pulse received.
Forward command pulse: Count up
Reverse command pulse: Count down
• The counting of the command pulse counter is stopped while the phase-Z or interrupt detection signal is "1."
Forward command pulse
Reverse command pulse
Phase-Z detecting
Interrupt detecting
Points of use:
· The increment of pulse count is calculated by the PC application program, using the following formula:
Increment = Previous value data - Current value data
· Because the maximum command pulse frequency of this module (NP1F-MP1/MP2) is 250kHz, the interval for
reading the increment value is shorter than the following value:
Sampling time < 32767 / 250kHz = 131ms
· When phase-Z (or interrupt signal) is detected, this module (NP1F-MP1/MP2) calculates the deviation amount
on the servo amplifier side from the command pulse counter value and detected position data.
On the CPU module side, 1/2 of the shift length is set in the command pulse register in advance, and the value
determined by subtracting the deviation amount from the remaining number of pulses when phase-Z
(or interrupt signal) is detected is added to the command pulse register to execute positioning.
(For a pulse command-type servo amplifier, the deviation counter is integrated in the amplifier. Therefore, the
moving length on the machine side after phase-Z or the interrupt signal is detected becomes as follows:)
Machine side moving length = Number of command pulses + Deviation amount
· Current command value data is output in current value data area 3. The content of current value data 3 is
continuously refreshed. Therefore, the control of current command value data from the CPU module is easy
when this area is referenced.
UP
Command
pulse counter
DOWN
(Forbidden)
Logical
sum
7-24