Set up MVX9000 to accept speed and direction
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20.03
Default: 01 -> 04 Master Frequency determined by RS485.

20.04
Default: 00 -> 03 Operating commands determined by the RS-485 communication
interface. Keypad STOP key is enabled.

50.01
Default: 01 -> 04 Master frequency determined by RS485

50.02
Default: 00 -> 03 Operating commands determined by the RS-485
communication interface. Keypad STOP key is enabled.

90.01
Default: 0 -> 3 Modbus RTU mode, <8,N,2>

90.02
Communication Address Range: 01 to 254
Default: 01

90.03
Default: 01 Baud rate 9600 (data transmission speed: bits / sec)

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Operationing Registers
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0705H
90.06 Communication frequency reference 0.0 to 400.0Hz

0706H
90.07 Communication command
Bit 0-1: 00 no function
         01 Stop
         10 Run
         11 JOG + Run
Bit 2-3:  Reserved
Bit 4-5: 00 no function
         01 Forward
         10 Reverse
         11 Change direction
Bit 6-15: Reserved

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HAL Pins
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Input
  Frequency
  Run/Stop
  Direction