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Hi , How do we get the size of RA

Hi , How do we get the size of RA

Hi , How do we get the size of RA

(OP)
Hi ,
 How do we get the size of RAM installed ?
 
BIOS (40:13) seems to store a 16-bit value, which is a
1k mutiple... With this scheme, it can represent not more
than 2^26.
 Sorry if i m wrong..

Is there any direct way of getting the amt of memory ??

RE: Hi , How do we get the size of RA

INT 15 - SYSTEM - later PS/2s - RETURN MEMORY-MAP INFORMATION
    AH = C7h
    DS:SI -> user supplied memory map table (see #0355)
Note:    call AH=C0h and examine bit 4 of feature byte 2 to check if this
      function is supported
Return: CF set on error, clear if successful
SeeAlso: AH=C0h,AH=C9h,AH=D1h

Format of memory-map table structure:
Offset    Size    Description    (Table 0355)
 00h    WORD  length of table (excluding this word)
 02h    DWORD local memory between 1M and 16M, in 1K blocks
 06h    DWORD local memory between 16M and 4G, in 1K blocks
 0Ah    DWORD system memory between 1M and 16M, in 1K blocks
 0Eh    DWORD system memory between 16M and 4G, in 1K blocks
 12h    DWORD cacheable memory between 1M and 16M, in 1K blocks
 16h    DWORD cacheable memory between 16M and 4G, in 1K blocks
 1Ah    DWORD 1K blocks before start of non-system memory between 1M and 16M
 1Eh    DWORD 1K blocks before start of non-system memory between 16M and 4G
 22h  2 DWORDs reserved




INT 15 - SYSTEM - GET EXTENDED MEMORY SIZE (286+)
    AH = 88h
Return: CF clear if successful
        AX = number of contiguous KB starting at absolute address 100000h
    CF set on error
        AH = status
        80h invalid command (PC,PCjr)
        86h unsupported function (XT,PS30)
Notes:    TSRs which wish to allocate extended memory to themselves often hook
      this call, and return a reduced memory size.    They are then free to
      use the memory between the new and old sizes at will.
    the standard BIOS only returns memory between 1MB and 16MB; use AH=C7h
      for memory beyond 16MB
    not all BIOSes correctly return the carry flag, making this call
      unreliable unless one first checks whether it is supported through
      a mechanism other than calling the function and testing CF
SeeAlso: AH=87h,AH=C7h

RE: Hi , How do we get the size of RA

(OP)
Hi MisterNobody,
 Thanx a lot for ur help. :)
Actually,i had written my own routine for calculating
memory size.The routine assumes a min of 2 MB. From 2MB,
i Start writing continously, until im unable to write any
more. At that stage, i decide upon memory size. Any way
i m glad to have this shortcut.
                Thanx a lot
regards,
Sarnath

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