CNCshield Squaring
References:
- CNC shield V1.9 schematic: [1]
CNC shield provides support for squaring via 2nd MEAG2560 pro mini device.
I used an alternative approach, by using Arduino Nano, which is inserted between CNC shield and the CNC mill.
The arduino Nano simply converts 4 input signals:
- PC0/A0: MEGA2560_STEP X1: puls signal, which controls pulses for stepper-driver for X-movement. Connected to U14.12
- PC1/A1: DIR X1: dir signal, which controls the direction for stepper-driver for x-movement. Connected to U14.5 and DRIVER DIR X1 (U14.4) and X2 (U17.15)
- PC2/A2: ESX1: endstop signal of X1 axis, connected to "Eingang 11"/U2.12
- PC2/A2: ESX2: endstop signal of X2 axis, connected to "Eingang 12"/U2.11
To 3 output signals:
- PB0/D8: Connected to STEP X1 driver (U14.14)
- PB1/D9: Connected to STEP X2 driver (U14.15)
- PB2/D10: Endstop X signal to MEGA2560_Eingang1. Connected to U2.24
ESX1/2 are connected as normally closed to GND (NC). JP-IN11/12 are configured to 5V (2/3). If the endstop switch is inactive (connection closed), Eingang11/12 are low.
MEGA2560_STEP X1 is forwarded to DRIVER STEP X1 as long as DIR points away from the endstops (high) OR ESX1 is not hit (low).
MEGA2560_STEP X2 is forwarded to DRIVER STEP X2 as long as DIR points away from the endstops (high) OR ESX2 is not hit (low).
MEGA2560_Eingang1 gets activated (high), when both ESX1 and ESX2 inputs are activated (high)
| PULS (A0) | DIR (A1) | ESX1 (A2) | ESX2 (A3) | inputval | PULS1 (PB0) | PULS2 (PB1) | Endstop (PB2) | outval |
| 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| 1 | 0 | 0 | 0 | 1 | 1 | 1 | 0 | 3 |
| 0 | 1 | 0 | 0 | 2 | 0 | 0 | 0 | 0 |
| 1 | 1 | 0 | 0 | 3 | 1 | 1 | 0 | 3 |
| 0 | 0 | 1 | 0 | 4 | 0 | 0 | 0 | 0 |
| 1 | 0 | 1 | 0 | 5 | 1 | 1 | 0 | 3 |
| 0 | 1 | 1 | 0 | 6 | 0 | 0 | 0 | 0 |
| 1 | 1 | 1 | 0 | 7 | 0 | 1 | 0 | 2 |
| 0 | 0 | 0 | 1 | 8 | 0 | 0 | 0 | 0 |
| 1 | 0 | 0 | 1 | 9 | 1 | 1 | 0 | 3 |
| 0 | 1 | 0 | 1 | 10 | 0 | 0 | 0 | 0 |
| 1 | 1 | 0 | 1 | 11 | 1 | 0 | 0 | 1 |
| 0 | 0 | 1 | 1 | 12 | 0 | 0 | 1 | 4 |
| 1 | 0 | 1 | 1 | 13 | 1 | 1 | 1 | 7 |
| 0 | 1 | 1 | 1 | 14 | 0 | 0 | 1 | 4 |
| 1 | 1 | 1 | 1 | 15 | 0 | 0 | 1 | 4 |