From: Damian Yerrick Newsgroups: comp.os.msdos.djgpp Subject: Re: DMA access Organization: Pin Eight Software http://pineight.8m.com/ Message-ID: References: <001301bf68c7$fe83e2e0$43fa4dc6 AT julianro> X-Newsreader: Forte Agent 1.7/32.534 MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Lines: 25 X-Trace: /Kw5eD8h5hy1afXRs7yC0IH8ebeN6ta0DDOHXPmem3sqYNslsobqC9Z9Hn9HbkeAdt8ZxY54OR3Y!wjvWONwqCyCwbxFGjieF/oQtRQuM6dWV+pJLhydf50x2pskPU4UFI3GkPwjhln2YgJwTD+zsDw== X-Complaints-To: abuse AT gte DOT net X-Abuse-Info: Please be sure to forward a copy of ALL headers X-Abuse-Info: Otherwise we will be unable to process your complaint properly NNTP-Posting-Date: Thu, 27 Jan 2000 18:05:53 GMT Distribution: world Date: Thu, 27 Jan 2000 18:05:53 GMT To: djgpp AT delorie DOT com DJ-Gateway: from newsgroup comp.os.msdos.djgpp Reply-To: djgpp AT delorie DOT com On Thu, 27 Jan 2000 08:10:36 -0500, "Julian Rolon" wrote: >faq states two methods for correct DMA accessig, one of these is >allocate a buffer in conventional memory with DPMI function >allocate_dos_memory but this function return a real mode segment >between 0000 and FFFF, How can i guarantee that segment returned >falls into Conventional memory?? Short answer: Don't worry. Longer answer: Real mode memory is 0x00000000-0x000fffff (1024 KB). Conventional memory is 0x00000000-0x0009ffff (640 KB). Upper memory blocks are any space in 0x000a0000-0x000fffff (384 KB) that is not used by adapter RAM or ROM. allocate_dos_memory will allocate a conventional memory block and then return the real mode segment that corresponds to the base of said block. -- Damian Yerrick http://yerricde.tripod.com/ Comment on story ideas: http://home1.gte.net/frodo/quickjot.html AOL is sucks! Find out why: http://anti-aol.org/faqs/aas/ View full sig: http://www.rose-hulman.edu/~yerricde/sig.html