From mboxrd@z Thu Jan 1 00:00:00 1970 From: Serdar Sutay Subject: Re: BCC, ELKS 24 Bit addressing mode Date: Thu, 23 Mar 2006 20:22:58 +0200 Message-ID: <4422E782.1030302@sentvion.com> References: <4422801D.2000006@sentvion.com> <4422EF6B.20804@gmail.com> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <4422EF6B.20804@gmail.com> Sender: linux-8086-owner@vger.kernel.org List-Id: Content-Type: text/plain; charset="us-ascii"; format="flowed" To: Segin Cc: Linux-8086@Vger.Kernel.Org Segin wrote: > Serdar Sutay wrote: > >> Dear All, >> >> I am porting ELKS to a special version of 80186 to be used in >> embedded devices. This special version known as Turbo186 is using 24 >> bit addressing using a special addressing scheme. So I need to modify >> bcc or as86 to support 24 bit addressing mode. >> >> This type of operation is common in embedded usage. 24 bit addressing >> is working like this, >> >> In normal 20 bit addressing when far jumps are used, two 16 bit >> operands are given for address calculation. First operand is left >> shifted 4 bits and added to second operand, then 20 bit address is >> calculated. >> >> In 24 bit addressing mode, first operand is left shifted 8 bits and >> added to second operand, resulting in 24 bit address. >> >> What am I required to do to support 24 bits addressing in bcc? Can >> you give me some insight or guide me to the correct person? >> >> Thank you for your consideration and help. >> >> Kindest regards, >> >> Serdar Sutay >> - >> To unsubscribe from this list: send the line "unsubscribe linux-8086" in >> the body of a message to majordomo@vger.kernel.org >> More majordomo info at http://vger.kernel.org/majordomo-info.html >> > Basically you're working with a 286 that's been lobotmized down to a > 186 with the addressing features in place? > > yes, but I need to address 16 Mbytes of RAM so I need to use 24 bit addressing mode. Can Bcc compiler handle this automatically?