USB-CDC: Increased buffer size to 256 bytes

cmaglie · cmaglie · commit 3127d1dc51e9 · 2016-08-24T12:50:25.000+02:00
This change improves read performance when massive data is sent
via USB by exploiting the hardware capability to handle multi-packet
transfers autonomously.
diff --git a/cores/arduino/USB/USBCore.cpp b/cores/arduino/USB/USBCore.cpp
@@ -427,7 +427,7 @@ void USBDeviceClass::initEP(uint32_t ep, uint32_t config)
 	}
 	else if (config == (USB_ENDPOINT_TYPE_BULK | USB_ENDPOINT_OUT(0)))
 	{
-		epHandlers[ep] = new DoubleBufferedEPOutHandler(usbd, ep, 64);
+		epHandlers[ep] = new DoubleBufferedEPOutHandler(usbd, ep, 256);
 	}
 	else if (config == (USB_ENDPOINT_TYPE_BULK | USB_ENDPOINT_IN(0)))
 	{

Original file line number	Diff line number	Diff line change
`@@ -427,7 +427,7 @@ void USBDeviceClass::initEP(uint32_t ep, uint32_t config)`
`427`	`427`	`}`
`428`	`428`	`else if (config == (USB_ENDPOINT_TYPE_BULK \| USB_ENDPOINT_OUT(0)))`
`429`	`429`	`{`
`430`		`- epHandlers[ep] = new DoubleBufferedEPOutHandler(usbd, ep, 64);`
	`430`	`+ epHandlers[ep] = new DoubleBufferedEPOutHandler(usbd, ep, 256);`
`431`	`431`	`}`
`432`	`432`	`else if (config == (USB_ENDPOINT_TYPE_BULK \| USB_ENDPOINT_IN(0)))`
`433`	`433`	`{`