From c44dc241600493fda64aa0ae985b883b5fd789e4 Mon Sep 17 00:00:00 2001
From: Paul Guenette <pfguenette@gmail.com>
Date: Sat, 29 Apr 2023 12:49:21 -0700
Subject: [PATCH] Add Bourns EMS22A SPI encoder

---
 Arduino/ODriveArduino/ODriveEnums.h | 1 +
 Firmware/MotorControl/encoder.cpp   | 6 ++++++
 Firmware/odrive-interface.yaml      | 3 +++
 tools/odrive/enums.py               | 2 ++
 4 files changed, 12 insertions(+)

diff --git a/Arduino/ODriveArduino/ODriveEnums.h b/Arduino/ODriveArduino/ODriveEnums.h
index 627c7b41..63527ec5 100644
--- a/Arduino/ODriveArduino/ODriveEnums.h
+++ b/Arduino/ODriveArduino/ODriveEnums.h
@@ -67,6 +67,7 @@ enum EncoderMode {
     ENCODER_MODE_SPI_ABS_AEAT                = 258,
     ENCODER_MODE_SPI_ABS_RLS                 = 259,
     ENCODER_MODE_SPI_ABS_MA732               = 260,
+    ENCODER_MODE_SPI_ABS_EMS22A              = 261,
 };
 
 // ODrive.Controller.ControlMode
diff --git a/Firmware/MotorControl/encoder.cpp b/Firmware/MotorControl/encoder.cpp
index 73771c34..08194313 100644
--- a/Firmware/MotorControl/encoder.cpp
+++ b/Firmware/MotorControl/encoder.cpp
@@ -494,6 +494,7 @@ void Encoder::sample_now() {
         case MODE_SPI_ABS_AEAT:
         case MODE_SPI_ABS_RLS:
         case MODE_SPI_ABS_MA732:
+        case MODE_SPI_ABS_EMS22A:
         {
             abs_spi_start_transaction();
             // Do nothing
@@ -595,6 +596,11 @@ void Encoder::abs_spi_cb(bool success) {
             pos = (rawVal >> 2) & 0x3fff;
         } break;
 
+        case MODE_SPI_ABS_EMS22A: {
+            uint16_t rawVal = abs_spi_dma_rx_[0];
+            pos = (rawVal >> 6) & 0x03ff;
+        } break;
+
         default: {
            set_error(ERROR_UNSUPPORTED_ENCODER_MODE);
            goto done;
diff --git a/Firmware/odrive-interface.yaml b/Firmware/odrive-interface.yaml
index 34cb09d0..9d60e4cb 100644
--- a/Firmware/odrive-interface.yaml
+++ b/Firmware/odrive-interface.yaml
@@ -1599,6 +1599,9 @@ valuetypes:
       SPI_ABS_MA732:
         value: 0x104
         doc: MagAlpha MA732 magnetic encoder
+      SPI_ABS_EMS22A:
+        value: 0x105
+        doc: Bourns EMS22A Non-Contacting Absolute Encoder
 
   ODrive.Controller.ControlMode:
     values:
diff --git a/tools/odrive/enums.py b/tools/odrive/enums.py
index 365facb8..5ee3d3a2 100644
--- a/tools/odrive/enums.py
+++ b/tools/odrive/enums.py
@@ -56,6 +56,7 @@ ENCODER_MODE_SPI_ABS_AMS                 = 257
 ENCODER_MODE_SPI_ABS_AEAT                = 258
 ENCODER_MODE_SPI_ABS_RLS                 = 259
 ENCODER_MODE_SPI_ABS_MA732               = 260
+ENCODER_MODE_SPI_ABS_EMS22A              = 261
 
 # ODrive.Controller.ControlMode
 CONTROL_MODE_VOLTAGE_CONTROL             = 0
@@ -214,6 +215,7 @@ class EncoderMode(enum.Enum):
     SPI_ABS_AEAT                             = 258
     SPI_ABS_RLS                              = 259
     SPI_ABS_MA732                            = 260
+    SPI_ABS_EMS22A                           = 261
 class ControlMode(enum.Enum):
     VOLTAGE_CONTROL                          = 0
     TORQUE_CONTROL                           = 1