hy_vfd(1)

💖 hy_vfd — the LinuxCNC manual page for the Huanyang VFD hookup 💖

okay so welcome to hy_vfd(1), bestie 🌸 this is the LinuxCNC Documentation page for it, and it's literally the thing that makes your Huanyang VFD talk to LinuxCNC. buckle up, it's giving ✨serial✨.

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✨ NAME ✨

hy_vfd — a HAL non-realtime component for Huanyang VFDs 🦋

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✨ SYNOPSIS ✨

hy_vfd [OPTIONS]

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✨ DESCRIPTION ✨

This component connects the Huanyang VFD to the LinuxCNC HAL via a serial (RS-485) connection. that's the whole vibe, fr fr 💅

The Huanyang VFD must be configured via the face plate user interface to accept serial communications. yes, with your actual hands, on the actual face plate. no cap. here's the whole checklist 👑

• PD001 = 2 — Set register PD001 (source of run commands) to 2 (communication port).
• PD002 = 2 — Set register PD002 (source of operating frequency) to 2 (communication port).
• PD004 — Set register PD004 (Base Frequency) according to motor specs. This is the rated frequency of the motor from the motor's name plate, in Hz.
• PD005 — Set register PD005 (max frequency) according to motor specs. This is the maximum frequency of the motor's power supply, in Hz.
• PD011 — Set register PD011 (min frequency) according to motor specs. This is the minimum frequency of the motor's power supply, in Hz.
• PD141 — Set register PD141 (rated motor voltage) according to motor name plate. This is the motor's maximum voltage, in Volts.
• PD142 — Set register PD142 (rated motor current) according to motor name plate. This is the motor's maximum current, in Ampere.
• PD143 — Set register PD143 (Number of Motor Poles) according to motor name plate.
• PD144 — Set register PD144 (rated motor revolutions) according to motor name plate. This is the motor's speed in RPM at 50 Hz. Note: This is not the motor's max speed (unless the max motor frequency happens to be 50 Hz)! 😭 read that twice bestie.
• PD163 = 1 — Set register PD163 (communication address) to 1. This matches the default in the hy_vfd driver, change this if your setup has special needs.
• PD164 = 2 — Set register PD164 (baud rate) to 2 (19200 bps). This matches the default in the hy_vfd driver, change this if your setup has special needs.
• PD165 = 3 — Set register PD165 (communication data method) to 3 (8n1 RTU). This matches the default in the hy_vfd driver, change this if your setup has special needs. Note that the hy_vfd driver only supports RTU communication, not ASCII. 🫶

Consult the Huanyang instruction manual for details on using the face plate to program the VFDs registers, and alternative values for the above registers. it's giving "read the other manual too" but that's just how it is 💜

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🔐 the "permission denied" saga (iykyk)

Access to devices such as /dev/ttyUSB0 is restricted to members of the "dialout" group. If you see error messages such as:

open: Permission denied
ERROR Can't open the device /dev/ttyUSB0 (errno 13)

Check your groups membership with the command:

groups

Then add your user to the dialout group with:

sudo addgroup your-username dialout

You will need to log out and back in again for this to take effect. yes, actually log out. not "close the terminal", log out. 💀

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✨ OPTIONS ✨

• -d, --device <path> — (default /dev/ttyS0) Set the name of the serial device node to use.
• -g, --debug — Turn on debug messages. Note that if there are serial errors, this may become annoying. Debug mode will cause all serial communication messages to be printed in hex on the terminal.
• -y, --regdump — Print the current value of all registers as soon as the VFD is enabled.
• -n, --name <string> — (default hy_vfd) Set the name of the HAL module. The HAL comp name will be set to <string>, and all pin and parameter names will begin with <string>.
• -b, --bits <n> — (default 8) Set number of data bits to <n>, where n must be from 5 to 8 inclusive. This must match the setting in register PD165 of the Huanyang VFD.
• -p, --parity [even,odd,none] — (default odd) Set serial parity to even, odd, or none. This must match the setting in register PD165 of the Huanyang VFD.
• -r, --rate <n> — (default 38400) Set baud rate to <n>. It is an error if the rate is not one of the following: 110, 300, 600, 1200, 2400, 4800, 9600, 19200, 38400, 57600, 115200. This must match the setting in register PD164 of the Huanyang VFD.
• -s, --stopbits [1,2] — (default 1) Set serial stop bits to 1 or 2. This must match the setting in register PD165 of the HuanyangVFD.
• -t, --target <n> — (default 1) Set HYCOMM target (slave) number. This must match the device number you set on the Hyanyang VFD in register PD163.
• -F, --max-frequency <n> — (default: read from VFD) If specified, program register PD005 of the VFD with the specified max frequency of <n> Hz (and use the same max frequency in the hy_vfd driver). If not specified, read the max frequency to use from register PD005 of the VFD.
• -f, --min-frequency <n> — (default: read from VFD) If specified, program register PD011 of the VFD with the specified minimum frequency of <n> Hz (and use the same minimum frequency in the hy_vfd driver). If not specified, read the minimum frequency to use from register PD011 of the VFD.
• -V, --motor-voltage <n> — (default: read from VFD) If specified, program register PD141 of the VFD with the specified max motor voltage of <n> Volts. If not specified, read the max motor voltage from register PD141 of the VFD.
• -I, --motor-current <n> — (default: read from VFD) If specified, program register PD142 of the VFD with the specified max motor current of <n> Amps. If not specified, read the max motor current from register PD142 of the VFD.
• -S, --motor-speed <n> — (default: compute from value read from VFD P144) This command-line argument is the motor's max speed. If specified, compute the motor's speed at 50 Hz from this argument and from the motor's max frequency (from the --max-frequency argument or from P011 if --max-frequency is not specified) and program register PD144 of the VFD. If not specified, read the motor's speed at 50 Hz from register P144 of the VFD, and use that and the max frequency to compute the motor's max speed.
• -P, --motor-poles <n> — (default: read value from VFD P143) This command-line argument is the number of poles in the motor. If specified, this value is sent to the VFD's register PD143. If not specified, the value is read from PD143 and reported on the corresponding HAL pin.
• -x, --register PDnnn=mmm <n> — Set a specific register to a new value. Can be used to set up to 10 registers. Parameters will "stick" (but only after hy_vfd.enable has been set true) so to set more than ten parameters it is possible to repeatedly load the driver with a set of registers to set then enable (setp hy_vfd.enable 1) and unload (unload hy_vfd) the driver at a halrun(1) prompt. For example:

loadusr -W hy_vfd -d /ttyUSB0 --register PD014=30 --register PD015=30

Will set both ramp1 times to 3 seconds. The values should be scaled according to the manual data. The example above uses values with a resolution of 0.1 seconds, so the numbers are 10x larger than the required value.

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✨ PINS ✨

• <name>.enable — (bit, in) Enable communication from the hy_vfd driver to the VFD.
• <name>.SetF — (float, out)
• <name>.OutF — (float, out)
• <name>.OutA — (float, out)
• <name>.Rott — (float, out)
• <name>.DCV — (float, out)
• <name>.ACV — (float, out)
• <name>.Cont — (float, out)
• <name>.Tmp — (float, out)
• <name>.spindle-forward — (bit, in)
• <name>.spindle-reverse — (bin, in)
• <name>.spindle-on — (bin, in)
• <name>.CNTR — (float, out)
• <name>.CNST — (float, out)
• <name>.CNST-run — (bit, out)
• <name>.CNST-jog — (bit, out)
• <name>.CNST-command-rf — (bit, out)
• <name>.CNST-running — (bit, out)
• <name>.CNST-jogging — (bit, out)
• <name>.CNST-running-rf — (bit, out)
• <name>.CNST-bracking — (bit, out)
• <name>.CNST-track-start — (bit, out)
• <name>.speed-command — (float, in)
• <name>.spindle-speed-fb — (float, out) Current spindle speed as reported by Huanyang VFD.
• <name>.spindle-at-speed-tolerance — (float, in) Spindle speed error tolerance. If the actual spindle speed is within .spindle-at-speed-tolerance of the commanded speed, then the .spindle-at-speed pin will go True. The default .spindle-at-speed-tolerance is 0.02, which means the actual speed must be within 2% of the commanded spindle speed.
• <name>.spindle-at-speed — (bit, out) True when the current spindle speed is within .spindle-at-speed-tolerance of the commanded speed.
• <name>.frequency-command — (float, out)
• <name>.max-freq — (float, out)
• <name>.base-freq — (float, out)
• <name>.freq-lower-limit — (float, out)
• <name>.rated-motor-voltage — (float, out)
• <name>.rated-motor-current — (float, out)
• <name>.rated-motor-rev — (float, out)
• <name>.motor-poles — (u32, out)
• <name>.hycomm-ok — (bit, out)

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✨ PARAMETERS ✨

• <name>.error-count — (s32, RW)
• <name>.retval — (float, RW)

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✨ AUTHOR ✨

Sebastian Kuzminsky 🫶

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✨ LICENSE ✨

GPL 👑

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and that's the whole page bestie!! this one came from the Huanyang VFD folks and it's dated April 25, 2015 — so like, a classic, an icon, a legend 💅✨ go forth and talk to your VFD fr fr 💖