LinuxCNC-RIO

RealtimeIO for LinuxCNC based on an FPGA

• no Soft-Core
• logic only
• no jitter
• fast and small
• communication via SPI (with Raspberry PI 4) or Ethernet
• generated verilog-code / setup via json files (free pin-selection)
• using free FPGA-Toolchain
• runs on many FPGA's (like ICE40, ECP5, MAX10, Artix7, Gwin, CycloneIV, ...)
• supports Open and Closed-Loop
• multiple and mixed joint types (like Stepper, DC-Servo, RC-Servo)

Sample-Configs:

Name	Description
TangNano9K	Tang Nano 9K with 5axis-BOB
Tango-Board	Tango-Board with Tang Nano 9K
Olimex-ICE40HX8K-EVB	Olimex ICE40HX8K-EVB with 5axis-BOB
TinyFPGA-BX	TinyFPGA-BX with 5axis-BOB
ICEBreakerV1.0e	ICEBreakerV1.0e tests
Lattice-iCE40HX8K	Lattice iCE40HX8K with custom bob
Colorlight5A-75E	Colorlight5A-75E tests
Alhambra-II	Alhambra II FPGA board with 3 Axis SPI
Altera10M08Eval	Altera10M08Eval with Arduino CNC-Shield v3
Arty-a7-35t	Arty-a7-35t with Arduino CNC-Shield v3
...	and many more

Plugins:

Type	Name	Description
joint	pwmdir	PWM Joint Output with DIR-Pin
joint	rcservo	RCSERVO Joint Output
joint	stepper	Stepper Joint Output with STEP/DIR/ENABLE(optional) pins
vin	frequency	Variable-Input for frequency measurement
vin	pulsecounter	Variable-Input for pulse counting with up to 3 pins (all optional)
vin	pwmcounter	Variable-Input for pulse width measurement
vin	quadencoder	Variable-Input for Quad-Encoder (int32_t)
vin	quadencoderz	Variable-Input for Quad-Encoder with Z-Pin (int32_t)
vin	sonar	Variable-Input for distance measurement via ultrasonic sonar sensor (HC-SR04)
vin	lm75	Variable-Input for temperature measurement via LM75 sensor
vin	ds18b20	Variable-Input for temperature measurement via DS18B20 sensor
vout	frequency	Variable-Output for frequencys
vout	pwm	Variable-Output for PWM-Signals with optional DIR pin
vout	sinepwm	Variable-Output for Sine-Waves via PWM-Signal
vout	spipoti	Variable-Output using digital poti with SPI Interface (like MCP413X/415X/423X/425X)
vout	udpoti	Variable-Output using digital poti with UpDown/Incr. Interface (like X9C104)
din	bit	Digital Input Pin (1bit)
dout	bit	Digital Output Pin (1bit)
expansion	shiftreg	Expansion to add I/O's via shiftregister's
expansion	shiftreg	Expansion to add I/O's via pcf8574 over I2C
interface	spislave	communication interface ( RPI(Master) <-SPI-> FPGA(Slave) )
...	...	and many more

FPGA-Toolchain:

https://github.com/YosysHQ/oss-cad-suite-build

for the TangNano9K, you can also using the Gowin-IDE or Gowin-Shell (it's faster)

interfacing with the raspberry

• Interface: SPI

• Chipselect: CE_1

• do not reuse the chipselect pin of your SPI-Flash !!!

interfacing via Ethernet

you can also use UDP2SPI bridge to communicate via Ethernet (UDP)

• WT32-ETH01
• ESP32-PoE-ISO
• ESP32_W5500

test-tool

if you want to test the connection without LinuxCNC, you can use the python test-tool:

python3 Output/BOARD_NAME/Gateware/qt_spitest.py [IP]

some hints

at the moment, you need at least configure one item of each of the following sections: vin, vout, din, dout, joints

buildtool

you can select a config via make argument:

make CONFIG=configs/TinyFPGA-BX/config.json build

Structure:

• buildtool.py plugins: python scripts to generates the verilog files from a configuration

• configs: here are the config files for a specific setup (Target-FPGA / Pins)

• Output: the generated files per config

some demo videos

LinuxCNC-Rio on MAX10 with CNC-Shield v3

LINUXCNC-RIO with W5500 on Max10 via UDP

LinuxCNC-RIO with TinyFPGA-BX and 5Axis BOB - ATC-Test

linuxcnc with tinyfpga-bx

Mini Closed-Loop DC-Servo on LinuxCNC-RIO

Linuxcnc RIO with ICEBreaker FPGA

LinuxCNC-RIO mixed joint types (on TangNano9K - FPGA)

LinuxCNC-RIO with TinyFPGA-BX and 5Axis BOB

LinuxCNC with ICE40 for stepgen

Linuxcnc RIO with Tang Nano 20k FPGA with esp32 and w5500 Ethernet

LinuxCNC-RIO mit CoreXY und Laser am PWM

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Thanks to the https://github.com/scottalford75/Remora Project, i'm using a modified version of it's Linux-Component

And many thanks for Contributions to:

• https://github.com/TurBoss
• https://github.com/ozzyrob
• https://github.com/jschoch
• https://github.com/festlv
• and all other