From 3322d48434b664ef6728e5c940d5c7253980626b Mon Sep 17 00:00:00 2001
From: Syed Asad Amin <s.asad.amin@gmail.com>
Date: Tue, 3 Aug 2021 21:25:27 +0500
Subject: [PATCH 1/2] Added support for One-Shot Mode (OSM)

---
 mcp2515.cpp | 11 +++++++++++
 mcp2515.h   |  5 +++++
 2 files changed, 16 insertions(+)

diff --git a/mcp2515.cpp b/mcp2515.cpp
index 6b86fb9..d1fa579 100644
--- a/mcp2515.cpp
+++ b/mcp2515.cpp
@@ -172,6 +172,9 @@ MCP2515::ERROR MCP2515::setNormalMode()
 
 MCP2515::ERROR MCP2515::setMode(const CANCTRL_REQOP_MODE mode)
 {
+    // Check for oneshot mode.
+    mode = osmFlag ? mode | CANCTRL_OSM : mode & ~(CANCTRL_OSM);
+
     modifyRegister(MCP_CANCTRL, CANCTRL_REQOP, mode);
 
     unsigned long endTime = millis() + 10;
@@ -764,3 +767,11 @@ uint8_t MCP2515::errorCountTX(void)
 {
     return readRegister(MCP_TEC);
 }
+
+void MCP2515::enableOSM(void) {
+    osmFlag = true;
+}
+
+void MCP2515::disableOSM(void) {
+    osmFlag = false;
+}
diff --git a/mcp2515.h b/mcp2515.h
index 5d9bef7..83bc87f 100644
--- a/mcp2515.h
+++ b/mcp2515.h
@@ -443,6 +443,7 @@ class MCP2515
         } RXB[N_RXBUFFERS];
 
         uint8_t SPICS;
+        bool osmFlag = false;
 
     private:
 
@@ -490,6 +491,10 @@ class MCP2515
         void clearERRIF();
         uint8_t errorCountRX(void);
         uint8_t errorCountTX(void);
+
+        // ONE SHOT MODE
+        void enableOSM(void);
+        void disableOSM(void);
 };
 
 #endif

From 596d8b0ddbac509c6b35fe1d565199910c0d55dd Mon Sep 17 00:00:00 2001
From: Syed Asad Amin <s.asad.amin@gmail.com>
Date: Fri, 6 Aug 2021 16:37:13 +0500
Subject: [PATCH 2/2] Bug fix for One-Shot Mode (OSM) support.

---
 mcp2515.cpp | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/mcp2515.cpp b/mcp2515.cpp
index d1fa579..90ef421 100644
--- a/mcp2515.cpp
+++ b/mcp2515.cpp
@@ -173,10 +173,13 @@ MCP2515::ERROR MCP2515::setNormalMode()
 MCP2515::ERROR MCP2515::setMode(const CANCTRL_REQOP_MODE mode)
 {
     // Check for oneshot mode.
-    mode = osmFlag ? mode | CANCTRL_OSM : mode & ~(CANCTRL_OSM);
+    uint8_t mcpMode = osmFlag ? mode | CANCTRL_OSM : mode & ~(CANCTRL_OSM);
 
-    modifyRegister(MCP_CANCTRL, CANCTRL_REQOP, mode);
+    // Writing CANCTRL register.
+    modifyRegister(MCP_CANCTRL, CANCTRL_REQOP, mcpMode);
 
+    // Checking from CANSTAT register only confirms the main working modes,
+    // and interrupts. Bit 4 is unimplemented.
     unsigned long endTime = millis() + 10;
     bool modeMatch = false;
     while (millis() < endTime) {