From mboxrd@z Thu Jan 1 00:00:00 1970 From: Gary Thomas To: Grant Edwards Cc: ecos Subject: Re: [ECOS] ARM vectors.S question Date: Wed, 27 Oct 1999 07:09:00 -0000 Message-id: References: <19991027090116.B14874@visi.com> X-SW-Source: 1999-10/msg00099.html On 27-Oct-99 Grant Edwards wrote: >> Firstly, you should consider working from the public CVS repository. This >> has the latest stuff in it, including much work that lets items such as >> this be specified in platform specific files, not directly in "vectors.S". > > OK, I'll take a look at the CVS tree -- having to modify what were > supposed to be platform-independant files made me think that I was > headed in the wrong direction. Are there semi-stable CVS snapshots, > or is a guy pretty much rolling the dice when using sources from the > CVS tree? > The public version of the CVS tree is updated from our working CVS about once a week. We try to keep the CVS tree in a constant working state since we have so much parallel development (the *!@# really flies when the tree gets broken :-) If you grab it today, you'll have a good version that shouldn't be more than a few days old. >> I'll try and provide help/guidance with whatever changes you need. >> Note that there are other places than "vectors.S" that expect low memory >> to be writeable so vectors can be updated. Unless you can take the >> "remap" route, there will be other considerations. > > Thanks. That's a very useful tip. I should be able to go either way: > remapping ROM/RAM in startup code or having ROM vectors go through > RAM. Initially I was thinking of sticking with the ROM vectors, but > it sounds like remapping might be a better idea. > Absolutely, remapping is the best [lowest cost/risk] way to do this. >> > I must say that the ARM load/store instructions are about the coolest >> > I've seen since the PDP-11. >> >> I shudder to think what you've been working with... > > Mostly the usual crop of embedded architectures (8086, 8051, 68HC11, > 68332) and the TI TMS32C320 DSP for a while [it was wierd having > sizeof (everyting) == 1]. > Yeuch! Let me (via the list) know if you have questions or problems.