From: address@hidden [mailto:address@hidden On Behalf Of Muhamad Ikhwan Ismail
Sent: Saturday, May 10, 2008 1:09 AM
To: Mailing list for lwIP users
Subject: RE: [lwip-users] Misalignment problems on PowerPC (little endian mode)
Hi Bill
Well I wish I could do it in big endian for the PowerPC, since the PowerPC corrects the alignment
problems in the hardware itself in big endian mode. Unfortunately the project itself requires me
to do it little endian. Which compiler did you use last time ?
Greetings
Ikhwan
> Date: Fri, 9 May 2008 17:30:10 +0200
> From: address@hidden
> To: address@hidden
> Subject: Re: [lwip-users] Misalignment problems on PowerPC (little endian mode)
>
> Muhamad Ikhwan Ismail wrote:
> >
> > Hi,
> >
> > Thanks Bill and Simon. Simon is right, my payload is aligned. The
> > problem arises when the Ethernet header
> > gets stripped, the IP addr field is not aligned when it gets accessed.
> > And I didnt know structure packing is a must. Then I have to
> > find a way to make my port works. Meaning even if i fixed my ip addr
> > processing macros and functions, Ill still get problems ?
> I'm not sure but I think so, yeah. The reason is the same reason
> 'network byte order' is used: when you exchange data over the network,
> everyone would have to use the same alignment. Instead, packing is used.
> > I thought i woulnt since all e.g TCP header fields are 2 bytes aligned ?
> At least DNS had a problem with non-packed mode, I think. DHCP could
> have problems, too...
>
> Simon
>
>
> _______________________________________________
> lwip-users mailing list
> address@hidden
> http://lists.nongnu.org/mailman/listinfo/lwip-users
With Windows Live for mobile, your contacts travel with you. Connect on the go.