1. allocation of memory
Is their a way to allocate a specific memory address in Eu ?
Can it be determined what address space is free to use in Eu ?
Thasnks Bernie Ryan
2. Re: allocation of memory
On Sun, 17 Jan 1999 12:02:11 -0500, Bernie Ryan <bwryan at PCOM.NET> wrote:
>Is their a way to allocate a specific memory address in Eu ?
>
>Can it be determined what address space is free to use in Eu ?
>
>Thasnks Bernie Ryan
p = allocate(100) will return an address pointing to 100 bytes
of free memory. The will be available until you do a free()
You can poke machine code into that memory, and call() the
code.
I don't think there is any way to control exactly where that
memory starts, however. Euphoria finds some unused space and
tells you where it is.
Irv
3. Re: allocation of memory
No I was looking for a way to allocate a specificate location
thanks irv
Bernie Ryan
4. Re: allocation of memory
- Posted by Pete Eberlein <xseal at HARBORSIDE.COM>
Jan 17, 1999
-
Last edited Jan 18, 1999
> No I was looking for a way to allocate a specificate location
>
> thanks irv
>
> Bernie Ryan
Perhaps you mean to convert a Physical Base Pointer into a Linear mapped
address... (isnt Protected Mode fun?) (not!)
lemme throw some machine code at ya... (this basically just calls an
interrupt, but using dos_interrupt absolutely will not work (dpmi service
calls don't seem to be available using that (Jacques Deschenes might
know more about this)))
constant linaddr = allocate(46)
poke(linaddr, {
#60, -- 0: pusha
#BB,#00,#00,#00,#00, -- 1: mov ebx, PhysBasePtr (2)
#89,#D9, -- 6: mov ecx, ebx
#C1,#EB,#10, -- 8: shr ebx, 16
#BE,#00,#00,#00,#00, -- B: mov esi, Size (12)
#89,#F7, -- 10: mov edi, esi
#C1,#EE,#10, -- 12: shr esi, 16
#B8,#00,#08,#00,#00, -- 15: mov eax, #800
#CD,#31, -- 1A: int #31
#C1,#E3,#10, -- 1C: shl ebx, 16
#66,#89,#CB, -- 1F: mov bx, cx
#89,#1D,#E2,#AF,#E4,#82,-- 22: mov [@linear], ebx
#61, -- 28: popa
#C3, -- 29: ret
#00,#00,#00,#00}) -- 2A: linear: dd 0 (42)
poke4(linaddr + 36, linaddr + 42) -- @linear
poke4(linaddr + 2, PhysBasePtr) ---- you supply these
poke4(linaddr + 12, Size) -- (size in bytes)
call(linaddr)
your linear address = peek4(linaddr + 42)
What is this good for? I've used it to get the VESA linear frame buffer,
perhaps it can be used to access other memory mapped devices...
Later dudez,
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5. Re: allocation of memory
>No I was looking for a way to allocate a specificate location
You *can* however, specify wether or not you want to allocate *low* or high*
memory.
And if you already know the exact memory addres, this means, some other
program/part does too. In which case, you dont need to allocate, you can
just poke & peek in that piece of memory.
Euphoria off course, doesnt 'allocate' memory already allocated by another
program.
Ralf
6. Re: allocation of memory
Thank You for information
