Set a baud rate limit for cdc-acm internally

bigdinotech · bigdinotech · commit 00f50b3f231c · 2017-10-26T09:41:22.000-07:00
-set a baud rate limit for cdc-acm due to the limitation of Inter Processor Mailbox
diff --git a/cores/arduino/CDCSerialClass.cpp b/cores/arduino/CDCSerialClass.cpp
@@ -86,8 +86,13 @@ void CDCSerialClass::begin(const uint32_t dwBaudRate, const uint8_t config)
 }
 
 
-void CDCSerialClass::init(const uint32_t dwBaudRate, const uint8_t modeReg)
+void CDCSerialClass::init(uint32_t dwBaudRate, const uint8_t modeReg)
 {
+    /* Set a max internal baud rate due to the limitation of the 
+     * Inter Processor Mailbox */
+     if(dwBaudRate > 115200)
+         dwBaudRate = 115200;
+    
     /* Set a per-byte write delay approximately equal to the time it would
      * take to clock out a byte on a standard UART at this baud rate */
     _writeDelayUsec = 8000000 / dwBaudRate;
diff --git a/cores/arduino/CDCSerialClass.h b/cores/arduino/CDCSerialClass.h
@@ -63,7 +63,7 @@ class CDCSerialClass : public HardwareSerial
     };
 
   protected:
-    void init(const uint32_t dwBaudRate, const uint8_t config);
+    void init(uint32_t dwBaudRate, const uint8_t config);
 
     uart_init_info *info;
     uint32_t _writeDelayUsec;

Original file line number	Diff line number	Diff line change
`@@ -86,8 +86,13 @@ void CDCSerialClass::begin(const uint32_t dwBaudRate, const uint8_t config)`
`86`	`86`	`}`
`87`	`87`
`88`	`88`
`89`		`-void CDCSerialClass::init(const uint32_t dwBaudRate, const uint8_t modeReg)`
	`89`	`+void CDCSerialClass::init(uint32_t dwBaudRate, const uint8_t modeReg)`
`90`	`90`	`{`
	`91`	`+ /* Set a max internal baud rate due to the limitation of the`
	`92`	`+ * Inter Processor Mailbox */`
	`93`	`+ if(dwBaudRate > 115200)`
	`94`	`+ dwBaudRate = 115200;`
	`95`	`+`
`91`	`96`	`/* Set a per-byte write delay approximately equal to the time it would`
`92`	`97`	`* take to clock out a byte on a standard UART at this baud rate */`
`93`	`98`	`_writeDelayUsec = 8000000 / dwBaudRate;`