Re: Simulating memory-mapped registers with SEH
1. Upon catching the exception, temporarily map a page, write data to the
desired location, and modify the exception record to do a single step.
2. When you get single step exception, unmap the page and clear single step
flag in the exception record.
3. Good luck with debugging that, though.
"Ulrich Eckhardt" <eckhardt@satorlaser.com> wrote in message
news:st7lo5-fuo.ln1@satorlaser.homedns.org...
Hi!
I'd like to simulate a register, similar to the memory-mapped IO registers
used by many embedded CPUs. Those are registers that are connected to an
integrated device but can be accessed by the normal memory access methods
for RAM.
For that, I thought I'd simply allocate a piece of virtual address space
without connecting any RAM to it. Then, when some code accesses that
address, I would expect to get an SEH notification caused by the access
violation. I would then perform the action according to the read or write
access and let the program continue. However, from what I have seen so
far,
I could only let the program continue if I actually remove the cause for
the violation, i.e. connect some storage to the virtual address, but that
means that the next access will also be able to use that storage and I
don't get a second notification.
I'm just wondering if what I want to do is possible at all and how big the
effort would be.
Thank you!
Uli
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