This is my little Arduino nano to parallel TB6560 cnc driver board project. Started some time ago using a red TB6560 4-axis board (before that i had an green 3-axis TB6560). At the moment the TB6560 alu case version is my preferred choice (but over time i can not remember why the red board was annoying me). The adapter should also work with 3-axis TB6560 boards if the Pinout is the same.
- KiCad files are included if you have special needs.
- Gerber files are included if you want to order your own pcb for e.g. at jlcpcb.com
- STL file of simple mount plate made with OpenSCAD is included if you have a 3d printer
Just work in progress current revision 1.4 using GRBL 1.1h.
- holes for resistors are to close for "normal" resistors. my fault this is my first pcb project. i choose a wrong footprint.
- silk outline for X, Y, Z leds on pcb has wrong orientation (my fault or bug in KiCad library?)
| Quantity | Pos | Part |
|---|---|---|
| 1 | pcb from pcb manufacturer of your choice | |
| 1 | J1 | DSUB-25 female horizontal |
| 5 | R1-R5 | 1k Ohm resistor |
| 1 | Q1 | 2N3904 transistor |
| 2 | SW1,SW2 | tactile push buttons 6x6 |
| 3 | D1-D3 | led 5mm |
| 5 | J3,J4,J6,J8,J9 | jumper header 2 pins |
| 3 | J2,J5,J7 | jumper header 3 pins |
| 5 | jumper | |
| 2 | 15 pin single row female straight header strip 2.54mm pitch for arduino nano |
| Picture | Revision | Comment |
|---|---|---|
 |
1.0 | first dirty revision to get rid of the spaghetti grbl adapter ;o) |
 |
1.1 | added jumper headers for the two versions (red pcb, alu case) of the TB6560 |
 |
1.2 | added two buttons for cycle start/resume and feed hold. added probe connector. added inverter circuit for spindle enable. |
 |
1.3 | added leds just for fun. |
| No real pcb image yet | 1.4 | fix wrong orientation of leds. fix wrong footprint of resistors. reroute affected tracks. |
| Arduino nano | GRBL 1.1 | DB25 red pcb | DB25 alu case version |
|---|---|---|---|
| D8 | Disable Stepper | 1 | 16 |
| D2 | X Step | 2 | 2 |
| D3 | Y Step | 4 (+8 A Step) | 4 (+8 A Step) |
| D4 | Z Step | 6 | 6 |
| D5 | X Dir | 3 | 3 |
| D6 | Y Dir | 5 (+9 A Dir) | 5 (+9 A Dir) |
| D7 | Z Dir | 7 | 7 |
| D9 | X Limit | 10 (IN1) | 10 (IN1) |
| D10 | Y Limit | 11 (IN2) | 11 (IN2) |
| D11 | Spindle Enable | 14 | 17 (see PWM invert!) |
| D12 | Z Limit | 12 (IN3) | 12 (IN3) |
| D13 | Spindle Dir | ||
| A0 | Reset/Abort | ||
| A1 | Feed/Hold | ||
| A2 | Cycle Start/Resume | ||
| A3 | Cooling Enable | ||
| GND | GND | 18-25 | 18-25 |
There are some jumpers to configure the board for the two used 4-axis board versions.
| Jumper | Description |
|---|---|
| J2 | connect Disable Stepper to pin 1* or pin 16** |
| J3 | connect Y Step pin 4 to A Step pin 8 |
| J4 | connect Y Dir pin 5 to A Dir pin 9 |
| J5 | connect Spindle PWM to pin 14* or pin 17** |
| J6 | Probe connector |
| J7 | use PWM, inverted PWM or disable (no jumper) |
| J8 | connector for alternative feed hold button |
| J9 | connector for alternative cycle start/resume button |
*red board version / **alu case version
TB6560 boards use low as spindle enable and high as spindel disable (WTF!?). It is the opposite way of how GRBL handle spindle enable/PWM. The used invert circuit will fix this. But there is a little gap where the invert is not active during startup/shutdown.
!!! As a workaround for now -> power on arduino at first and power off at last again to prevent injury through spindle.
Sources:
- How to setup inverting PWM signal and using +5v to switch off spindle motor? · Issue #22 · gnea/grbl · GitHub
- GRBL PWM inverter circuit
- Explain the Logic NOT Gate or Inverter and its Operation with Truth Table
$$
$0=10
$1=25
$2=0
$3=5
$4=0
$5=0
$6=0
$10=1
$11=0.010
$12=0.002
$13=0
$20=0
$21=0
$22=0
$23=0
$24=25.000
$25=500.000
$26=250
$27=1.000
$30=1000
$31=0
$32=0
$100=402.000
$101=402.000
$102=402.000
$110=1500.000
$111=1500.000
$112=750.000
$120=42.000
$121=42.000
$122=42.000
$130=2000.000
$131=2000.000
$132=2000.000
G38.2 z-10 f1
http://www.linuxcnc.org/docs/2.6/html/gcode/gcode.html#sec:G38-probe
G92 z19.2
http://www.linuxcnc.org/docs/2.6/html/gcode/gcode.html#sec:G92
Evaluate gcodes to test with bCNC custom user button.
G38.2 z-100 f5
G92 z19.7
G0 z50 f600
Download, extract and copy GRBL to the Arduino library. More details see here: https://github.com/gnea/grbl/wiki/Compiling-Grbl
Arduino IDE settings:
- Tools -> Board -> "Arduino Nano"
- Tools -> Processor -> "ATmega328P (Old Bootloader)"
- Tools -> Port -> "/dev/ttyUSB0" (may vary)
- Tools -> Programer -> "Atmel-ICE(AVR)"
| GRBL PWM enabled | GRBL |
|---|---|
 |
 |
Just for info. Interesting board with much faster cpu and more memory. https://github.com/usbcnc/grbl
