Re: [f-cpu] More Dark and Dusty Corners

[Ben Franchuk <bfranchuk@jetnet.ab.ca>]

Juergen Goeritz wrote:
> 
> Maybe from the debugging interface?
> 
> > In a simple privilege model (user/supervisor only), the register should
> > be invisible.  In the capabilities model, there might be a bit that
> > turns access privileges on and off independently.
> 
> Why not add another mode for access that may be switched
> on from 'outside' to go into hardware debugging mode?
> 
 Why is a virtual cpu needed on the first revision? I don't mind
slow interrupt service providing hardware is defined for it -
dma access and fifo's where needed. The serial port on the PC (
the whole pc) is a bad example of doing interrupts. What is
needed is smart - dumb hardware i/o controllers. If you you
define a virtual machine lets define virtual hardware that is
clean and works well. Bring back I/O control blocks? Pesudo
fixed memory frame buffers? More real time smarts.
Ben. 

-- 
Standard Disclaimer : 97% speculation 2% bad grammar 1% facts.
"Pre-historic Cpu's" http://www.jetnet.ab.ca/users/bfranchuk
Now with schematics.
*************************************************************
To unsubscribe, send an e-mail to majordomo@seul.org with
unsubscribe f-cpu       in the body. http://f-cpu.seul.org/