1 files changed, 10 insertions, 7 deletions
diff --git a/testhal/STM32/STM32F4xx/USB_CDC_IAD/main.c b/testhal/STM32/STM32F4xx/USB_CDC_IAD/main.c
index 7827acf47..486942104 100644
--- a/testhal/STM32/STM32F4xx/USB_CDC_IAD/main.c
+++ b/testhal/STM32/STM32F4xx/USB_CDC_IAD/main.c
@@ -26,12 +26,6 @@
 
 #include "usbcfg.h"
 
-/*
- * Virtual serial ports over USB.
- */
-SerialUSBDriver SDU1;
-SerialUSBDriver SDU2;
-
 /*===========================================================================*/
 /* Command line related.                                                     */
 /*===========================================================================*/
@@ -90,6 +84,7 @@ static void cmd_test(BaseSequentialStream *chp, int argc, char *argv[]) {
   chThdWait(tp);
 }
 
+/* Can be measured using dd if=/dev/xxxx of=/dev/null bs=512 count=10000.*/
 static void cmd_write(BaseSequentialStream *chp, int argc, char *argv[]) {
   static uint8_t buf[] =
       "0123456789abcdef0123456789abcdef0123456789abcdef0123456789abcdef"
@@ -116,7 +111,15 @@ static void cmd_write(BaseSequentialStream *chp, int argc, char *argv[]) {
   }
 
   while (chnGetTimeout((BaseChannel *)chp, TIME_IMMEDIATE) == Q_TIMEOUT) {
-    chSequentialStreamWrite(&SDU1, buf, sizeof buf - 1);
+#if 1
+    /* Writing in channel mode.*/
+    chnWrite(&SDU1, buf, sizeof buf - 1);
+#else
+    /* Writing in buffer mode.*/
+    (void) obqGetEmptyBufferTimeout(&SDU1.obqueue, TIME_INFINITE);
+    memcpy(SDU1.obqueue.ptr, buf, SERIAL_USB_BUFFERS_SIZE);
+    obqPostFullBuffer(&SDU1.obqueue, SERIAL_USB_BUFFERS_SIZE);
+#endif
   }
   chprintf(chp, "\r\n\nstopped\r\n");
 }