Subject: Re: [stella] Alpha Source From: "Thomas Jentzsch" <tjentzsch@xxxxxx> Date: Wed, 17 Jan 2001 15:50:00 +0100 |
Hi Manuel, in your Alpha Source you wrote >; here's the routine >; to convert from standard X positions to FC positions. >; Could a good man explain me how it works? It is basicaly doing a divsion by 15. You need this, because before hitting RESxx, normaly you are using a coarse delay loop which needs 5 cycles/loop and every cpu cycle is equal to 3 pixel (-> 3 * 5 = 15). The division by 15 is replaced by a divsion by 16 (you know why:) with an additional correction. Very clever! The code returns the coarse value in Y and the fine value for HMxx in A. You can use both values directly or OR them into a single variable for later use. Thomas Jentzsch | *** Every bit is sacred ! *** tjentzsch at web dot de | ______________________________________________________________________________ Die Fachpresse ist sich einig: WEB.DE 16mal Testsieger! Kostenlos E-Mail, Fax, SMS, Verschlüsselung, POP3, WAP....testen Sie uns! http://freemail.web.de -- Archives (includes files) at http://www.biglist.com/lists/stella/archives/ Unsub & more at http://www.biglist.com/lists/stella/
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