Now I cant find my order status on there site, I think its been cancelled! You'd swear they dont want my money!
Ill have to give them a call.
Ill have to give them a call.
Last edited by Jepeto87 (2007-07-12 10:06:33)
Last edited by Jepeto87 (2007-07-12 10:06:33)
Mail order FTW! (NOT).Jepeto87 wrote:
Now I cant find my order status on there site, I think its been cancelled! You'd swear they dont want my money!
Ill have to give them a call.
First up - appologies for not replying sooner - been reading up...ph4s3 wrote:
That's nice. While we're comparing penis size credentials here, I've got a BSEE, have passed my first Professional Engineer license exam and I have developed the hardware and firmware for several embedded systems using MMIO. Granted, they were 16bit and not x86 architecture, but the principles of MMIO are still the same.Scorpion0x17 wrote:
WHAT?!ph4s3 wrote:
I don't believe that is correct. The BIOS maps address space to devices and doesn't use the system RAM that is displaced. in a 4GB address space, if all 4GB are installed, whatever is mapped to the devices is effectively unmapped from the system RAM so those particular locations will never be accessible.
If you have 3GB of system RAM installed and a 700MB memory footprint, then all 3GB of physical system RAM are addressable and usable, the 700MB of device-mapped memory is addressable, and there's still 300MB or so of address space left available. However, if you have 4GB of physical system RAM installed and the same 700MB footprint, the 700MB device-mapped memory is addressable and only 3.3GB of physical RAM is addressable, the other 700MB of space on the system RAM doesn't have an address and can't be used.
The BIOS effectively uses that address space, but it is not using the physical system RAM when it maps memory pointers to installed devices.
I'm sorry but you clearly don't know enough about what you're talking about.
B.I.O.S. Stands for Basic Input Output System. It is the BIOS that handles ALL the IO - this is done using space within physical memory addresses, and it is all co-ordinated by the BIOS.
Look, I have a BTEC in Computer Studies, A-Level Computer Studies and a BEng(Hons) degree in Software Engineering for Real-Time Systems. I'm not saying this to say "I'm better than you" - I'm saying it because whilst gaining these qualifications I learnt all about how IO and memory mapping works at the hardware level and I, therefore, do know exactly what I'm talking about.
If you've got a certain size address space and your physical memory is the same size, when you use MMIO you lose access to the memory stack for whatever quantity of addresses you map to the I/O registers because those addresses no longer point at the stack. The way you put it makes it sound as if some part of that physical RAM is used by the BIOS when it isn't. It's wasted because the addresses that could use it are reserved and pointing somewhere else and if data were loaded to those addresses it would go to the I/O bus to whatever device has that address assigned to it.
Perhaps I got the verbiage wrong in regards to the function of the BIOS doing a particular task, but MMIO doesn't get any simpler than that. You lose whatever you map elsewhere because one address can't go to two different locations.
And that means you can't get access to 4GB of system RAM on modern computers (x86 types with a 32bit OS), because a portion of that 4GB address space is remapped to the devices in the PC such as the video card.
Last edited by Scorpion0x17 (2007-07-13 16:52:05)
Nowhere near enough for my liking.Manicalwizard wrote:
Off topic, how much does everyone think the prices will go down after july 22?
About this much...Manicalwizard wrote:
Off topic, how much does everyone think the prices will go down after july 22?