;***************************************************************************
; 
; File Name		:'STEPPER.asm"
; Title			:
; Date			:
; Version		:
; Support telephone	:765 287 1987  David B. VanHorn
; Support fax		:765 287 1989
; Support Email		:dvanhorn@cedar.net
; Target MCU		:AT90S8515
; 
;***************************************************************************;
;	M O D I F I C A T I O N   H I S T O R Y 
;
;
;       rev.      date    who   why
;	----	--------  ---	------------------------------------------
;	0.01	98.08.30  dvh	Creation
;	0.02	98.09.03  dvh	More info on how to electrically drive steppers
;
;********************************************************************
;
;
;A simple routine to control a stepper motor. 
;Full or half-step, outputs designed for unipolar motors.
;Outputs on port A, bits 0-3
;
;Full stepping
;
;Phase	Current
;
;0000	1	(off)
;1000	1	1st state
;0100	1
;0010	1
;0001	1	4th state
;
;Half-Stepping
;
;Phase  Current
;
;0000	0	(off)
;1000	1	1st state
;1100	0
;0100	1
;0110	0
;0010	1
;0011	0
;0001	1
;1001	0	8th state
;
;
;	ULN2003 driver IC  (2803 is similar, but one more driver, and 2 more pins)
;
;     Inputs   Outputs
;
;	1 ----> 16  High input = low output (coil active)
;	2 ----> 15
;	3 ----> 14	
;	4 ----> 13	
;	5 ----> 12	
;	6 ----> 11	
;	7 ----> 10	
;   GND	8	9 Diode 
;
;
;
;Each driver sinks current when it's input is at a logic high. Each driver has a 
;protection diode, all diodes come to pin 9, which should be connected to the 
;stepper's +V supply.
;For this application, connect the AVR stepper output pins to pins 1,2,3,4 of 
;the 2003, pin 8 of the IC to the development board's ground, and 16,15,14,13 
;of the 2003 to the stepper's coil leads. Connect the two common leads of the
;stepper to pin 9, and apply a modest voltage (3-6V) from an external power supply. 
;Be sure to tie the external supply ground to the development board ground.
;
;This IC uses the stepper's coil resistance to limit the applied current, so be sure
;that your stepper supply voltage does not exceed the current rating of the chip, or 
;the thermal limits of the motor. Rare earth magnet steppers can be permanently "cooked"
;by applying too much power for too long.  The chip's own voltage limit is 50V, but the
;curent limit and thermal limits are much more important.  The IC is rated for 500mA max.
;
;A good treatment on stepper motors is available at:
;http://www.cs.uiowa.edu/~jones/step/circuits.html
;
;Going forward, step up the table, going backward, step back :)
;Up to 1mS per step (or half-step) with a simple control routine based on the 1mS ISR
;
;Ram variables
;
;Step_Dir	Forward or reverse (0=Reverse, 1=forward, anything else= no step)?
;Step_Time	mS per phase (0-255)
;Step_State	Where are we now? A pointer into the stepper output table
;Step_Mode	Full or half step (0=full 1=half)
;Step_Speed	Reload value for Step_Time. Your application can change this and 
;		alter the stepper speed. Beware, steppers don't like large changes
;		in velocity.
;
Step_Motor: ;First, see if we're stepping this time
	lds	TEMP,Step_Time	;Is it time to step?
	cpi	TEMP,$00	;
	breq	Step_Direction	;If so, then check direction, else
	ret			;just bail


Step_Direction: ;Then determine the direction
	lds	TEMP,Step_Dir	;Get the current direction
	and	TEMP,TEMP	;
	breq	Step_Reverse	;
	cpi	TEMP,$01	;Is it forward?
	breq	Step_Forward	;Go if so.
	rjmp	Step_Done	;else it's no step


Step_Forward: ;Then wether full or half (forward)
	lds	TEMP,Step_Mode	;Full or half
	and	TEMP,TEMP	;
	breq	Step_FF		;
	rjmp	Step_FH		;

Step_Reverse: ;Or wether full or half (reverse)
	lds	TEMP,Step_Mode	;Full or half?
	and	TEMP,TEMP	;
	breq	Step_RF		;
	rjmp	Step_RH		;
;
;***************************************************************************************
;
;Step forard, a full step
;
Step_FF:
	lds	TEMP,Step_State			;Get the current state
	inc	TEMP				;advance one step on the full step table
	cpi	TEMP,$04			;
	brne	Step_FFA			;
	ldi	TEMP,$00			;
Step_FFA:
	ldi	ZL,low(Full_Step_Table*2)	;Make the Z reg point at the table
	ldi	ZH,high(Full_Step_Table*2)	;preparing for the LPM instruction
	rjmp	Step_Output			;
;
;Step forward, a half step
;
Step_FH:
	lds	TEMP,Step_State			;Get the current state
	inc	TEMP				;advance one step on the full step table
	cpi	TEMP,$08			;
	brne	Step_FHA			;
	ldi	TEMP,$00			;
Step_FHA:
	ldi	ZL,low(Half_Step_Table*2)	;Make the Z reg point at the table
	ldi	ZH,high(Half_Step_Table*2)	;preparing for the LPM instruction
	rjmp	Step_Output			;
;
;Step reverse a full step
;
Step_RF:
	lds	TEMP,Step_State			;Get the current state
	dec	TEMP				;advance one step on the full step table
	cpi	TEMP,$FF			;
	brne	Step_RFA			;
	ldi	TEMP,$03			;

Step_RFA:
	ldi	ZL,low(Full_Step_Table*2)	;Make the Z reg point at the table
	ldi	ZH,high(Full_Step_Table*2)	;preparing for the LPM instruction
	rjmp	Step_Output			;
;
;Step reverse a half step
;
Step_RH:
	lds	TEMP,Step_State			;Get the current state
	dec	TEMP				;advance one step on the full step table
	cpi	TEMP,$FF			;
	brne	Step_RHA			;
	ldi	TEMP,$07			;
Step_RHA:
	ldi	ZL,low(Half_Step_Table*2)	;Make the Z reg point at the table
	ldi	ZH,high(Half_Step_Table*2)	;preparing for the LPM instruction
	rjmp	Step_Output			;
;
;Whichever and how far, output the motor states
;
Step_Output:
	sts	Step_State,TEMP			;
	lsl	TEMP				;Mult x 2, because we store words in rom
	add	ZL,TEMP				;Add the calculated offset
	brcc	STO_A				;If no carry, then we're done
	inc	ZH				;Handle carry

STO_A:	lpm					;look up character
	mov	TEMP,R0				;
	andi	TEMP,$0F			;Mask off non-stepper bits
	in	TEMP2,PORTA			;
	andi	TEMP2,$F0			;Kill old stepper bits
	or	TEMP2,TEMP			;
	out	PORTA,TEMP2			;

Step_Done:

	lds	TEMP,Step_Rate			;Restart the timer for the next step
	sts	Step_Time,TEMP			;
	ret					;


<!--'"</title></head>-->

<script type="text/javascript">
//OwnerIQ
var __oiq_pct = 50;
if( __oiq_pct>=100 || Math.floor(Math.random()*100/(100-__oiq_pct)) > 0 ) {
var _oiqq = _oiqq || [];
_oiqq.push(['oiq_addPageBrand','Lycos']);
_oiqq.push(['oiq_addPageCat','Internet > Websites']);
_oiqq.push(['oiq_addPageLifecycle','Intend']);
_oiqq.push(['oiq_doTag']);
(function() {
var oiq = document.createElement('script'); oiq.type = 'text/javascript'; oiq.async = true;
oiq.src = document.location.protocol + '//px.owneriq.net/stas/s/lycosn.js';
var s = document.getElementsByTagName('script')[0]; s.parentNode.insertBefore(oiq, s);
})();
}
//Google Analytics
var _gaq = _gaq || [];
_gaq.push(['_setAccount','UA-21402695-19']);
_gaq.push(['_setDomainName','tripod.com']);
_gaq.push(['_setCustomVar',1,'member_name','stelios_cellar',3]);
_gaq.push(['_trackPageview']);
(function() {
var ga = document.createElement('script'); ga.type = 'text/javascript'; ga.async = true;
ga.src = ('https:' == document.location.protocol ? 'https://ssl' : 'http://www') + '.google-analytics.com/ga.js';
var s = document.getElementsByTagName('script')[0]; s.parentNode.insertBefore(ga, s);
})();
//Lycos Init
function getReferrer() {
var all= this.document.cookie;
if (all== '') return false;
var cookie_name = 'REFERRER=';
var start = all.lastIndexOf(cookie_name);
if (start == -1) return false;
start += cookie_name.length;
var end = all.indexOf(';', start);
if (end == -1) end = all.length;
return all.substring(start, end);
}
function getQuery() {
var rfr = getReferrer();
if (rfr == '') return false;
var q = extractQuery(rfr, 'yahoo.com', 'p=');
if (q) return q;
q = extractQuery(rfr, '', 'q=');
return q ? q : "";
}
function extractQuery(full, site, q_param) {
var start = full.lastIndexOf(site);
if (start == -1) return false;
start = full.lastIndexOf(q_param);
if (start == -1) return false;
start += q_param.length;
var end = full.indexOf('&', start);
if (end == -1) end = full.length;
return unescape(full.substring(start, end)).split(" ").join("+");
}
function generateHref(atag, template){
atag.href=template.replace('_MYURL_', window.location.href.replace('http://', '')).replace('_MYTITLE_','Check%20out%20this%20Tripod%20Member%20site!'); 
}
var lycos_ad = Array();
var lycos_onload_timer;
var cm_role = "live";
var cm_host = "tripod.lycos.com";
var cm_taxid = "/memberembedded";
var tripod_member_name = "stelios_cellar";
var tripod_member_page = "Stelios_Cellar/AVR/FileArchive/Source/GetStart/stepper.asm";
var tripod_ratings_hash = "1714132362:2e9cbca14e0500e2305623ba27140b76";

var lycos_ad_category = {"find_what":"e scripts md;1"};

var lycos_ad_remote_addr = "209.202.244.9";
var lycos_ad_www_server = "www.tripod.lycos.com";
var lycos_ad_track_small = "";
var lycos_ad_track_served = "";
var lycos_search_query = getQuery();
</script>

<script type="text/javascript" src="https://scripts.lycos.com/catman/init.js"></script>

<script type='text/javascript'>
 var googletag = googletag || {};
 googletag.cmd = googletag.cmd || [];
 (function() {
   var gads = document.createElement('script');
   gads.async = true;
   gads.type = 'text/javascript';
   var useSSL = 'https:' == document.location.protocol;
   gads.src = (useSSL ? 'https:' : 'http:') +
     '//www.googletagservices.com/tag/js/gpt.js';
   var node = document.getElementsByTagName('script')[0];
   node.parentNode.insertBefore(gads, node);
 })();
</script>

<script type='text/javascript'>
 googletag.cmd.push(function() {
   googletag.defineSlot('/95963596/TRI_300X250_dfp', [300, 250], 'div-gpt-ad-1450204159126-0').addService(googletag.pubads());
   googletag.defineSlot('/95963596/TRI_above_728x90_dfp', [728, 90], 'div-gpt-ad-1450204159126-1').addService(googletag.pubads());
   googletag.defineSlot('/95963596/TRI_below_728x90_dfp', [728, 90], 'div-gpt-ad-1450204159126-2').addService(googletag.pubads());
   googletag.pubads().enableSingleRequest();
   googletag.enableServices();
 });
</script>


<script type="text/javascript"> 
(function(isV)
{
    if( !isV )
    {
        return;
    }
    var adMgr = new AdManager();
    var lycos_prod_set = adMgr.chooseProductSet();
    var slots = ["leaderboard", "leaderboard2", "toolbar_image", "toolbar_text", "smallbox", "top_promo", "footer2", "slider"];
    var adCat = this.lycos_ad_category;
    adMgr.setForcedParam('page', (adCat && adCat.dmoz) ? adCat.dmoz : 'member');
    if (this.lycos_search_query)
    {
        adMgr.setForcedParam("keyword", this.lycos_search_query);
    } 
    else if(adCat && adCat.find_what)
    {
        adMgr.setForcedParam('keyword', adCat.find_what);
    }
    
    for (var s in slots)
    {
        var slot = slots[s];
        if (adMgr.isSlotAvailable(slot))
        {
            this.lycos_ad[slot] = adMgr.getSlot(slot);
        }
    }

    adMgr.renderHeader();
    adMgr.renderFooter();
}((function() {

var w = 0, h = 0, minimumThreshold = 300;

if (top == self)
{
    return true;
}
if (typeof(window.innerWidth) == 'number' )
{
    w = window.innerWidth;
    h = window.innerHeight;
}
else if (document.documentElement && (document.documentElement.clientWidth || document.documentElement.clientHeight))
{
    w = document.documentElement.clientWidth;
    h = document.documentElement.clientHeight;
}
else if (document.body && (document.body.clientWidth || document.body.clientHeight))
{
    w = document.body.clientWidth;
    h = document.body.clientHeight;
}
return ((w > minimumThreshold) && (h > minimumThreshold));
}())));




window.onload = function()
{
    var f = document.getElementById("FooterAd");
    var b = document.getElementsByTagName("body")[0];
    b.appendChild(f);
    f.style.display = "block";
    document.getElementById('lycosFooterAdiFrame').src = '/adm/ad/footerAd.iframe.html';
    


    
    // DOM Inj Ad
    (function(isTrellix)
    {
        var e = document.createElement('iframe');
        e.style.border = '0';
        e.style.margin = 0;
        e.style.display = 'block';
        e.style.cssFloat = 'right';
        e.style.height = '254px';
        e.style.overflow = 'hidden';
        e.style.padding = 0;
        e.style.width = '300px';


        var isBlokedByDomain = function( href )
        {
            var blockedDomains = [
                "ananyaporn13000.tripod.com",
                "xxxpornxxx.tripod.com"
            ];
            var flag = false;
            
            for( var i=0; i<blockedDomains.length; i++ )
            {
                if( href.search( blockedDomains[ i ] ) >= 0 )
                {
                    flag = true;
                }
            }
            return flag;
        }

        var getMetaContent = function( metaName )
        {
            var metas = document.getElementsByTagName('meta');
            for (i=0; i<metas.length; i++)
            { 
                if( metas[i].getAttribute("name") == metaName )
                { 
                    return metas[i].getAttribute("content"); 
                } 
            }
            return false;
        }
        
        var getCommentNodes = function(regexPattern)
        {
            var nodes = {};
            var nodesA = [];
            var preferredNodesList = ['a', 'c', 'b'];
        
            (function getNodesThatHaveComments(n, pattern)
            {
                if (n.hasChildNodes())
                {
                    if (n.tagName === 'IFRAME')
                    {
                        return false;
                    }
                    for (var i = 0; i < n.childNodes.length; i++)
                    {
                        if ((n.childNodes[i].nodeType === 8) && (pattern.test(n.childNodes[i].nodeValue)))
                        {
                            var areaName = pattern.exec(n.childNodes[i].nodeValue)[1];
                            nodes[areaName] = n;
                        }
                        else if (n.childNodes[i].nodeType === 1)
                        {
                            getNodesThatHaveComments(n.childNodes[i], pattern);
                        }
                    }
                }
            }(document.body, regexPattern));

            for (var i in preferredNodesList)
            {
                if (nodes[preferredNodesList[i]])
                {
                    if( isTrellix && nodes[preferredNodesList[i]].parentNode.parentNode.parentNode.parentNode )
                    {
                        nodesA.push(nodes[preferredNodesList[i]].parentNode.parentNode.parentNode.parentNode);
                    }
                    else
                    {
                        nodesA.push( nodes[preferredNodesList[i]] );
                    }
                }
            }
            return nodesA;
        }
        
        
        var properNode = null;
        var areaNodes = getCommentNodes( new RegExp( '^area Type="area_(\\w+)"' ) );

        for (var i = 0; i < areaNodes.length; i++)
        {
            var a = parseInt(getComputedStyle(areaNodes[i]).width);
            if ((a >= 300) && (a <= 400))
            {
                properNode = areaNodes[i];
                break;
            }
        }


        var propertyName = getMetaContent("property") || false;
        if( isTrellix && (properNode) )
        {
            e.src = '/adm/ad/injectAd.iframe.html';
            properNode.insertBefore(e, properNode.firstChild);
        }
        else if( isTrellix && !( properNode ) ) // Slap the ad eventhought there is no alocated slot
        {
            e.src = '/adm/ad/injectAd.iframe.html';
            e.style.cssFloat = 'none';
            var cdiv = document.createElement('div');
            cdiv.style = "width:300px;margin:10px auto;";
            cdiv.appendChild( e );
            b.insertBefore(cdiv, b.lastChild);
        }
        else if( !isBlokedByDomain( location.href ) )
        {
            var injF = document.createElement('iframe');
            injF.style.border = '0';
            injF.style.margin = 0;
            injF.style.display = 'block';
            injF.style.cssFloat = 'none';
            injF.style.height = '254px';
            injF.style.overflow = 'hidden';
            injF.style.padding = 0;
            injF.style.width = '300px';
            injF.src = '/adm/ad/injectAd.iframe.html';

            if( b && ( !isTrellix || ( typeof isTrellix == "undefined" ) ) ) // All other tripod props
            {
                var cdiv = document.createElement('div');
                cdiv.style = "width:300px;margin:10px auto;";
                cdiv.appendChild( injF );
                b.insertBefore(cdiv, b.lastChild);
            } 
        }
  }( document.isTrellix ));
}

</script>

<div id="tb_container" style="background:#DFDCCF; border-bottom:1px solid #393939; position:relative; z-index:999999999!important">
<!--form name="search" onSubmit="return searchit()" id='header_search' >
<input type="text" placeholder="Search" size=30 name="search2" value="">
<input type="button" value="Go!" onClick="searchit()">
</form>
<style>
form#header_search {
    width: 916px;
    margin: 0 auto 8px;
    position: relative;
}


form#header_search input {
    height: 40px;
    font-size: 14px;
    line-height: 40px;
    padding: 0 8px;
    box-sizing: border-box;
    background: #F4F2E9;
    border: 1px solid #BBB8B8;
    transition: background-color 300ms ease-out,
                color 300ms ease;
}

form#header_search input[type="text"] {
    width: 100%;
}
form#header_search input[type="text"]:focus {
    border-color: #A2D054;
    background-color: #fff;
    box-shadow: 0 0px 12px -4px #A2D054;
}



form#header_search input[type="button"] {
    position: absolute;
    top: 1px;
    right: 1px;
    opacity: 1;
    background: #DFDCCF;
    color: #463734;
    width: 125px;
    cursor: pointer;
    height: 38px;
    border: none;
}
form#header_search input[type="text"]:focus ~ input[type='button']:hover,
form#header_search input[type='button']:hover {
    background-color: #A5CE56;
    color: #fff;
}
form#header_search input[type="text"]:focus ~ input[type='button'] {
    background-color: #52AEDF;
    color: #fff;
}

</style>

<script>
function searchit(){
    
    // determine environment 
    var search_env 
    if (lycos_ad_www_server.indexOf(".pd.") > -1) {
       search_env = 'http://search51.pd.lycos.com/a/';
    } else if (lycos_ad_www_server.indexOf(".qa.") > -1) {
       search_env = 'http://search51.qa.lycos.com/a/';
    } else {
       search_env = 'http://search51.lycos.com/a/';
    }

var search_term = encodeURIComponent(document.search.search2.value)
var search_url = search_env+search_term;
window.open(search_url);

return false
}
</script-->
<style>
    .adCenterClass{margin:0 auto}
</style>
<div id="tb_ad" class="adCenterClass" style="display:block!important; overflow:hidden; width:916px;">

<div id="ad_container" style="display:block!important; float:left; width:728px ">
<script type="text/javascript">
if (typeof lycos_ad !== "undefined" && "leaderboard" in lycos_ad) {
  document.write(lycos_ad['leaderboard']);
}
</script>
</div>
</div>
</div>
<script type="text/javascript">
if (typeof lycos_ad !== "undefined" && "slider" in lycos_ad) {
  document.write(lycos_ad['slider']);
}
</script> <!-- added 7/22 -->
<div id="FooterAd" style="background:#DFDCCF; border-top:1px solid #393939; clear:both; display:none; width:100%!important; position:relative; z-index:999999!important; height:90px!important"> 
<div class="adCenterClass" style="display:block!important; overflow:hidden; width:916px;">
<div id="footerAd_container" style="display:block!important; float:left; width:728px">
<iframe id="lycosFooterAdiFrame" style="border:0; display:block; float:left; height:96px; overflow:hidden; padding:0; width:750px"></iframe>
</div>
</div>
</div>