From e940d6ad43e2af6ec9d44d711e3ef89d11b34768 Mon Sep 17 00:00:00 2001 From: patacongo Date: Sun, 21 Nov 2010 15:48:25 +0000 Subject: expand a comment git-svn-id: svn://svn.code.sf.net/p/nuttx/code/trunk@3123 42af7a65-404d-4744-a932-0658087f49c3 --- nuttx/arch/arm/src/lpc17xx/lpc17_ethernet.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) (limited to 'nuttx/arch') diff --git a/nuttx/arch/arm/src/lpc17xx/lpc17_ethernet.c b/nuttx/arch/arm/src/lpc17xx/lpc17_ethernet.c index 72fc5de38..21e60feb6 100644 --- a/nuttx/arch/arm/src/lpc17xx/lpc17_ethernet.c +++ b/nuttx/arch/arm/src/lpc17xx/lpc17_ethernet.c @@ -1462,7 +1462,13 @@ static int lpc17_ifup(struct uip_driver_s *dev) lpc17_putreg(ETH_RXINTS, LPC17_ETH_INTEN); #endif - /* Enable Rx */ + /* Enable Rx. "Enabling of the receive function is located in two places. + * The receive DMA manager needs to be enabled and the receive data path + * of the MAC needs to be enabled. To prevent overflow in the receive + * DMA engine the receive DMA engine should be enabled by setting the + * RxEnable bit in the Command register before enabling the receive data + * path in the MAC by setting the RECEIVE ENABLE bit in the MAC1 register." + */ regval = lpc17_getreg(LPC17_ETH_CMD); regval |= ETH_CMD_RXEN; -- cgit v1.2.3