added RS485 communication with VFD

Readme.md

@@ -34,6 +34,8 @@
 *   **Limit Sensors:** 3x **LJ12A3-4-Z/BX** (Inductive NPN NO).
 *   *Note: The PiBot V4.7 features built-in 0-10V analog output and opto-isolated inputs, eliminating the need for separate converter modules and isolation boards.*
 
+![PiBot FluidNC GRBL Laser CNC Controller V4.7B top](images/PiBot_Board_top.jpg)  
+![PiBot FluidNC GRBL Laser CNC Controller V4.7B bottom](images/PiBot_Board_bottom.png)
 ### Power System (Dual PSU)
 *   **Motion Power:** Mean Well **LRS-350-24** (24V, 350W) for Drivers.
 *   **Logic Power:** Mean Well **MDR-20-24** (24V, 20W DIN Rail) for PiBot Board & Sensors.
@@ -90,8 +92,8 @@ The PiBot V4.7 uses 5V logic shifting for axis signals. The following diagram il
 ### D. Spindle Control (0-10V Direct)
 The PiBot V4.7 includes an integrated 0-10V circuit.
 
-**Signal Connection:**
-*   Locate the **10V Spindle Interface** terminal on the PiBot.
+**1. 0-10V Signal Connection**
+Locate the **10V Spindle Interface** terminal on the PiBot.
 
 | PiBot Output | VFD Terminal | Function |
 | :--- | :--- | :--- |
@@ -101,6 +103,22 @@ The PiBot V4.7 includes an integrated 0-10V circuit.
 | **out2/Rev** | **REV** | Reverse Signal |
 | **out common** | **DCM** | Digital Common |
 
+**2. RS485 Implementation Detail (4-Core Shielded)**
+It allows for digital precision (no voltage drift), real-time RPM feedback, and the ability to monitor VFD temperature and current via the FluidNC Web UI.  
+To ensure zero-error communication at 24,000 RPM, the RS485 cable must be paired as follows:
+
+1. **Signal Pair:** [RS+] and [RS-] must share a single twisted pair to maximize differential noise cancellation.
+2. **Reference Pair:** Both wires of the remaining twisted pair are joined for [GND] to provide a stable common-mode reference between the PiBot and VFD logic.
+3. **Shielding:** The drain wire/braid is connected to the VFD Earth terminal (PE) only. The PiBot side of the shield is left floating (cut and insulated) to prevent ground loops.
+4. VFD Config (Huanyang):
+Set PD001=2 and PD002=2 for RS485 control.
+Set PD163=1, PD164=1, PD165=3 for 9600 baud communication.
+5. Wiring:
+PiBot [A] → VFD [RS+]
+PiBot [B] → VFD [RS-]
+PiBot [GND] → VFD [DCM] (If required)
+Shield → VFD PE (Earth Ground screw)
+
 ### E. Probe (GX12)
 *   **Pin 1 (GND):** Alligator Clip.
 *   **Pin 2 (Signal):** Touch Plate (Connect to PiBot Probe Input).
@@ -162,6 +180,7 @@ For **1.5kW, 220V, 400Hz** spindle:
 | **PD005** | Max Freq | **400.0** | |
 | **PD004** | Base Freq | **400.0** | **CRITICAL:** Do not leave at 50/60. |
 | **PD003** | Main Freq | **400.0** | |
+| **PD011** | Min Freq | **100** | Lowest spped 6,000 RPM Safety Limit |
 | **PD141** | Rated Voltage | **220** | |
 | **PD142** | Rated Current | **5** | |
 | **PD143** | Motor Poles | **2** | High-speed CNC spindles are 2-pole. |

config.yaml

@@ -27,7 +27,7 @@ axes:
       feed_scaler: 1.100
 
     motor0:
-      limit_neg_pin: gpio.34:low
+      limit_neg_pin: gpio.26:low
       limit_pos_pin: NO_PIN
       limit_all_pin: NO_PIN
       hard_limits: false
@@ -54,7 +54,7 @@ axes:
       feed_scaler: 1.100
 
     motor0:
-      limit_neg_pin: gpio.39:low
+      limit_neg_pin: gpio.33:low
       limit_pos_pin: NO_PIN
       limit_all_pin: NO_PIN
       hard_limits: false
@@ -82,7 +82,7 @@ axes:
 
     motor0:
       limit_neg_pin: NO_PIN
-      limit_pos_pin: gpio.36:low
+      limit_pos_pin: gpio.32:low
       limit_all_pin: NO_PIN
       hard_limits: false
       pulloff_mm: 1.000
@@ -133,34 +133,34 @@ coolant:
 ################################################################################################################################
 
 # Begin Huanyang RS485
-# uart1:
-#   txd_pin: gpio.15
-#   rxd_pin: gpio.16
-#   rts_pin: gpio.14
-#   baud: 9600
-#   mode: 8N1
+uart1:
+  txd_pin: gpio.15
+  rxd_pin: gpio.16
+  rts_pin: gpio.14
+  baud: 9600
+  mode: 8N1
 
-# Huanyang:
-#   uart_num: 1
-#   modbus_id: 1
-#   tool_num: 1
-#   speed_map: 0=0% 0=25% 6000=25% 24000=100%
-#   off_on_alarm: false
+Huanyang:
+  uart_num: 1
+  modbus_id: 1
+  tool_num: 1
+  speed_map: 0=0% 0=25% 6000=25% 24000=100%
+  off_on_alarm: true
 
 # Begin 10V
-10V:
-  forward_pin: gpio.15
-  reverse_pin: gpio.14
-  pwm_hz: 5000
-  output_pin: gpio.13
-  enable_pin: NO_PIN
-  direction_pin: NO_PIN
-  disable_with_s0: false
-  s0_with_disable: true
-  spinup_ms: 0
-  spindown_ms: 0
-  tool_num: 0
-  speed_map: 0=0.000% 1000=0.000% 24000=100.000%
-  off_on_alarm: false
+# 10V:
+#   forward_pin: gpio.15
+#   reverse_pin: gpio.14
+#   pwm_hz: 5000
+#   output_pin: gpio.13
+#   enable_pin: NO_PIN
+#   direction_pin: NO_PIN
+#   disable_with_s0: false
+#   s0_with_disable: true
+#   spinup_ms: 0
+#   spindown_ms: 0
+#   tool_num: 0
+#   speed_map: 0=0% 6000=25% 24000=100%
+#   off_on_alarm: false
 
 # End of File