Hi Marty, I know that the max recommended setting for the EMC clock is 80MHz. Unfortunately I am limited on my board to a 16 bit data-bus to SDRAM, however I ran extensive comprehensive memory tests at that higher frequency, and everything seems to be OK.
On Thu, Jan 9, 2014 at 1:00 AM, <lwip-users-requ...@nongnu.org> wrote: > Send lwip-users mailing list submissions to > lwip-users@nongnu.org > > To subscribe or unsubscribe via the World Wide Web, visit > https://lists.nongnu.org/mailman/listinfo/lwip-users > or, via email, send a message with subject or body 'help' to > lwip-users-requ...@nongnu.org > > You can reach the person managing the list at > lwip-users-ow...@nongnu.org > > When replying, please edit your Subject line so it is more specific > than "Re: Contents of lwip-users digest..." > > Today's Topics: > > 1. Re: missing TX packets (Pomeroy, Marty) > > > ---------- Forwarded message ---------- > From: "Pomeroy, Marty" <martypome...@novabio.com> > To: "Mailing list for lwIP users" <lwip-users@nongnu.org> > Cc: > Date: Tue, 7 Jan 2014 14:27:37 -0500 > Subject: Re: [lwip-users] missing TX packets > > * Don't run EMCCLK above 80MHz! * > > On the datasheet for the LPC178x/7x, page 84 and 85 shows that Tcy has a > minimum of 12.5ns, which translates to a maximum EMC Clock of 80MHz. We > found out the hard way that it may work on most LPC1788s, but not on some! > Not recommended to run it above spec. > > Our product using LPC1788 has LCD at max refresh rate, AND running the > program itself out of DRAM, and no trouble with Ethernet. Not sure where > to look for issues... make sure everything is using 32 bit transfers and > DRAM is configured as a 32 bit interface... > > > > ------------------------------ > *From:* lwip-users-bounces+martypomeroy=novabio....@nongnu.org [mailto: > lwip-users-bounces+martypomeroy=novabio....@nongnu.org] *On Behalf Of *Lehel > Benedek > *Sent:* Sunday, January 05, 2014 7:45 PM > *To:* lwip-users@nongnu.org > *Subject:* Re: [lwip-users] missing TX packets > > I managed to fix the problem by increasing the EMC clock rate from 60Mhz > to 104Mhz and lowering the refresh rate of the LCD. The LCD controller was > eating up all my bandwith to the external memory. Now both the webserver > and the LCD are working nicely. > Thanks for your help. > > > > > _______________________________________________ > lwip-users mailing list > lwip-users@nongnu.org > https://lists.nongnu.org/mailman/listinfo/lwip-users >
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