path: root/public/posts/drum-sequencer/index.html

<!doctype html><html lang=en><head><meta charset=utf-8><meta content="width=device-width,initial-scale=1.0" name=viewport><title>Making a Drum Sequencer - Venkata Rao Dechiraju</title><meta content="I always looked at Teenage Engineering and thought it was pretty cool and given I have a sem break right now, I thought I can make one too. shouldn’t be hard ri…" name=description><link href=https://veradec.xyz/posts/drum-sequencer/ rel=canonical><link href=https://veradec.xyz/favicon/favicon.ico rel=icon type=image/x-icon><link href=https://veradec.xyz/favicon/favicon-16x16.png rel=icon sizes=16x16 type=image/png><link href=https://veradec.xyz/favicon/favicon-32x32.png rel=icon sizes=32x32 type=image/png><link href=https://veradec.xyz/favicon/apple-touch-icon.png rel=apple-touch-icon sizes=180x180><link href=https://veradec.xyz/favicon/site.webmanifest rel=manifest><link as=style href=https://veradec.xyz/style.css rel=preload><link href=https://cdn.jsdelivr.net/npm/katex@0.16.9/dist/katex.min.css rel=stylesheet><script defer src=https://cdn.jsdelivr.net/npm/katex@0.16.9/dist/katex.min.js></script><script onload="renderMathInElement(document.body, {
        delimiters: [
          {left: '$$', right: '$$', display: true},
          {left: '$', right: '$', display: false}
        ]
      });" defer src=https://cdn.jsdelivr.net/npm/katex@0.16.9/dist/contrib/auto-render.min.js></script><meta content="blog, tech, programming" name=keywords><meta content="Venkata Rao Dechiraju" name=author><meta content="index, follow" name=robots><meta content=#1e3a8a name=theme-color><meta content=article property=og:type><meta content=https://veradec.xyz/posts/drum-sequencer/ property=og:url><meta content="Making a Drum Sequencer" property=og:title><meta content="I always looked at Teenage Engineering and thought it was pretty cool and given I have a sem break right now, I thought I can make one too. shouldn’t be hard ri…" property=og:description><meta content="Venkata Rao Dechiraju" property=og:site_name><meta content=https://veradec.xyz/static/banner.png property=og:image><meta content=summary_large_image name=twitter:card><meta content="Making a Drum Sequencer" name=twitter:title><meta content="I always looked at Teenage Engineering and thought it was pretty cool and given I have a sem break right now, I thought I can make one too. shouldn’t be hard ri…" name=twitter:description><meta content=https://veradec.xyz/static/banner.png name=twitter:image><script type=application/ld+json>
    {
      "@context": "https://schema.org",
      "@type": "WebSite",
      "name": "Venkata Rao Dechiraju",
      "url": "https:&#x2F;&#x2F;veradec.xyz&#x2F;",
      "description": "made by a actual human"
      
      ,"author": {
        "@type": "Person",
        "name": "Venkata Rao Dechiraju"
        
        ,"url": "https:&#x2F;&#x2F;verade.xyz"
        
      }
      
    }
    </script><link title="atom feed for Venkata Rao Dechiraju" href=https://veradec.xyz/atom.xml rel=alternate type=application/atom+xml><link title="rss feed for Venkata Rao Dechiraju" href=https://veradec.xyz/rss.xml rel=alternate type=application/rss+xml><link href=https://veradec.xyz/style.css rel=stylesheet><script type=application/ld+json>
{
  "@context": "https://schema.org",
  "@type": "BlogPosting",
  "headline": "Making a Drum Sequencer",
  "url": "https:&#x2F;&#x2F;veradec.xyz&#x2F;posts&#x2F;drum-sequencer&#x2F;"
  
  ,"datePublished": "2026-05-27T00:00:00Z"
  
  
  
  ,"author": {
    "@type": "Person",
    "name": "Venkata Rao Dechiraju"
    
    ,"url": "https:&#x2F;&#x2F;verade.xyz"
    
  }
  
}
</script><body><div class=background-container><img alt class=background-image src=Raja_Ravi_Varma,_Sakunthala_Pathralekhan.jpg></div><div aria-label="Reading progress" class=reading-progress id=reading-progress role=progressbar></div><a class=skip-to-content href=#content>skip to content</a><div class=wrap><header><a href=https://veradec.xyz/ id=home-link> <span aria-hidden=true id=back-icon> <svg viewbox="0 0 24 24" fill=none stroke=currentColor stroke-linecap=round stroke-linejoin=round stroke-width=2><polyline points="15 18 9 12 15 6"></polyline></svg> </span> <span id=back-text>back</span> </a></header><div id=content><div class=hero><h1>Making a Drum Sequencer</h1><div class=hero-meta><span> Wed May 27, 2026 </span><span>·</span><span>2 min read</span><span>·</span><span>375 words</span></div></div><nav aria-label="Table of contents" class=table-of-contents><div class=toc-header><span class=toc-title>Contents</span></div><ul class=toc-list><li class=toc-item><a class=toc-link data-target=the-design href=#the-design>The Design</a><li class=toc-item><a class=toc-link data-target=the-prototyping href=#the-prototyping>The Prototyping</a></ul></nav><script>'use strict';
    
    (function() {
        const toc = document.querySelector('.table-of-contents');
        if (!toc) return;
        
        function initTableOfContents() {
            const links = document.querySelectorAll('.toc-link');
            
            if (!links.length) return;

            requestAnimationFrame(() => {
                toc.classList.add('visible');
            });

            const headingMap = new Map();
            let observerInstance = null;
            
            links.forEach(link => {
                const targetId = link.dataset.target;
                const heading = document.getElementById(targetId);
                if (heading) {
                    headingMap.set(targetId, { link, heading });
                }
            });

            const observerOptions = {
                rootMargin: '-40% 0px -50% 0px',
                threshold: 0
            };

            observerInstance = new IntersectionObserver((entries) => {
                entries.forEach(entry => {
                    if (entry.isIntersecting) {
                        links.forEach(link => link.classList.remove('toc-link--active'));
                        
                        const targetId = entry.target.id;
                        const item = headingMap.get(targetId);
                        if (item) {
                            item.link.classList.add('toc-link--active');
                        }
                    }
                });
            }, observerOptions);

            headingMap.forEach(({ heading }) => {
                observerInstance.observe(heading);
            });

            const cleanup = () => {
                if (observerInstance) {
                    observerInstance.disconnect();
                    observerInstance = null;
                }
            };

            window.addEventListener('beforeunload', cleanup);
            window.addEventListener('pagehide', cleanup);
        }
        
        if (document.readyState === 'loading') {
            document.addEventListener('DOMContentLoaded', initTableOfContents);
        } else {
            initTableOfContents();
        }
    })();</script><article><p>I always looked at Teenage Engineering and thought it was pretty cool and given I have a sem break right now, I thought I can make one too. shouldn’t be hard right?<br> and after i started composing music, Techno was a genre I always wanted to try but i couldn’t, and then an idea popped up, maybe I can create a suite of instruments<blockquote><p>a Synth</blockquote><blockquote><p>a Drum Sequencer</blockquote><blockquote><p>a Vocoder</blockquote><p>and start making techno on them? Sounds nice innit?<br> <br><h1 id=the-design>The Design</h1><p>I wanted the design to look a little retro 80’s esque, and I wanted it to be little simpler (because I will have suite of appliances to generate different sounds, so would rather have one that is simple and does it job well) and I drew a few sketches and ended with something that looks very nice<div style=justify-content:center;display:flex><img alt="Drum Sequencer Rough Sketch" src=/dq_sketch.png style=width:50%;transform:rotate(-90deg)></div><h1 id=the-prototyping>The Prototyping</h1><p>with the <em>beautifully</em> crafted picture in hand, now the plan is to prototype<p>I needed around 16 Buttons – which I am going to pull of some keyboards i archived (They paid off innit?).<p>I might need to get some more potentiometers and find a way to make a matrix the LEDs and Buttons, Once That is done, Getting the whole thing shouldn’t be that tough (atleast I hope it isn’t)</article></div><div class=bottom-menu><p><a href=/posts>posts</a> <a href=/about>about</a> <a href=https://github.com/veradec>github</a> <a href=/authors>authors</a> <a href=/tags>tags</a> <a href=/categories>categories</a></div><button aria-label="Scroll to top" id=scroll-to-top><svg viewbox="0 0 24 24" aria-hidden=true fill=none stroke=currentColor stroke-linecap=round stroke-linejoin=round stroke-width=2><polyline points="18 15 12 9 6 15"></polyline></svg></button><footer><div class=sam-footer>Built using Zola & Prism theme</div></footer></div><script>'use strict';

(function() {
    const SVG_ICONS = {
        copy: '<svg viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" aria-hidden="true"><rect x="9" y="9" width="13" height="13" rx="2" ry="2"></rect><path d="M5 15H4a2 2 0 0 1-2-2V4a2 2 0 0 1 2-2h9a2 2 0 0 1 2 2v1"></path></svg>',
        check: '<svg viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" aria-hidden="true"><polyline points="20 6 9 17 4 12"></polyline></svg>',
        error: '<svg viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" aria-hidden="true"><line x1="18" y1="6" x2="6" y2="18"></line><line x1="6" y1="6" x2="18" y2="18"></line></svg>'
    };

    function debounce(func, wait) {
        let timeout;
        return function executedFunction(...args) {
            clearTimeout(timeout);
            timeout = setTimeout(() => func(...args), wait);
        };
    }

    function initNavigation() {
        try {
            const homeLink = document.getElementById('home-link');
            const backIcon = document.getElementById('back-icon');
            const backText = document.getElementById('back-text');
            
            if (!homeLink) return;
            
            const homeText = 'back';
            const isHomePage = window.location.pathname === '/' || window.location.pathname === '/index.html';
            
            if (backIcon && isHomePage) {
                backIcon.style.display = 'none';
            }
            
            if (backText) {
                backText.textContent = homeText;
            }
            
            homeLink.setAttribute('aria-label', `Go to ${homeText.toLowerCase()} page`);
        } catch (error) {
            console.error('Navigation init failed:', error);
        }
    }

    function initScrollToTop() {
        try {
            const scrollToTopBtn = document.getElementById('scroll-to-top');
            if (!scrollToTopBtn) return;
            
            const prefersReducedMotion = window.matchMedia('(prefers-reduced-motion: reduce)').matches;
            
            const toggleVisibility = debounce(() => {
                if (window.scrollY > 300) {
                    scrollToTopBtn.classList.add('visible');
                } else {
                    scrollToTopBtn.classList.remove('visible');
                }
            }, 100);
            
            window.addEventListener('scroll', toggleVisibility, { passive: true });
            toggleVisibility();
            
            scrollToTopBtn.addEventListener('click', () => {
                window.scrollTo({
                    top: 0,
                    behavior: prefersReducedMotion ? 'auto' : 'smooth'
                });
            });
        } catch (error) {
            console.error('Scroll to top init failed:', error);
        }
    }

    
    function initCopyCodeButtons() {
        try {
            const codeBlocks = document.querySelectorAll('pre code');
            
            codeBlocks.forEach((codeBlock) => {
                const pre = codeBlock.parentElement;
                
                const wrapper = document.createElement('div');
                wrapper.className = 'code-block-wrapper';
                pre.parentNode.insertBefore(wrapper, pre);
                wrapper.appendChild(pre);
                
                const copyButton = document.createElement('button');
                copyButton.className = 'copy-code-button';
                copyButton.innerHTML = SVG_ICONS.copy;
                copyButton.setAttribute('aria-label', 'Copy code to clipboard');
                copyButton.setAttribute('title', 'Copy code');
                
                wrapper.appendChild(copyButton);
                
                copyButton.addEventListener('click', async () => {
                    const code = codeBlock.textContent;
                    
                    try {
                        if (navigator.clipboard && window.isSecureContext) {
                            await navigator.clipboard.writeText(code);
                        } else {
                            const textArea = document.createElement('textarea');
                            textArea.value = code;
                            textArea.style.position = 'fixed';
                            textArea.style.left = '-999999px';
                            document.body.appendChild(textArea);
                            textArea.select();
                            document.execCommand('copy');
                            document.body.removeChild(textArea);
                        }
                        
                        copyButton.innerHTML = SVG_ICONS.check;
                        copyButton.classList.add('copied');
                        copyButton.setAttribute('aria-label', 'Code copied');
                        
                        setTimeout(() => {
                            copyButton.innerHTML = SVG_ICONS.copy;
                            copyButton.classList.remove('copied');
                            copyButton.setAttribute('aria-label', 'Copy code to clipboard');
                        }, 2000);
                    } catch (err) {
                        console.error('Failed to copy code:', err);
                        
                        copyButton.innerHTML = SVG_ICONS.error;
                        copyButton.classList.add('error');
                        copyButton.setAttribute('aria-label', 'Copy failed');
                        
                        setTimeout(() => {
                            copyButton.innerHTML = SVG_ICONS.copy;
                            copyButton.classList.remove('error');
                            copyButton.setAttribute('aria-label', 'Copy code to clipboard');
                        }, 2000);
                    }
                });
            });
        } catch (error) {
            console.error('Copy code buttons init failed:', error);
        }
    }
    

    
    function initSmoothScroll() {
        try {
            const prefersReducedMotion = window.matchMedia('(prefers-reduced-motion: reduce)').matches;
            if (prefersReducedMotion) return;
            
            document.querySelectorAll('a[href^="#"]').forEach(anchor => {
                anchor.addEventListener('click', function (e) {
                    const href = this.getAttribute('href');
                    if (href === '#' || href.length <= 1) return;
                    
                    e.preventDefault();
                    const target = document.querySelector(href);
                    
                    if (target) {
                        const offset = 80;
                        const targetPosition = target.getBoundingClientRect().top + window.pageYOffset - offset;
                        
                        window.scrollTo({
                            top: targetPosition,
                            behavior: 'smooth'
                        });
                        
                        if (window.history.pushState) {
                            window.history.pushState(null, null, href);
                        }
                        
                        if (!target.hasAttribute('tabindex')) {
                            target.setAttribute('tabindex', '-1');
                        }
                        target.focus({ preventScroll: true });
                    }
                });
            });
        } catch (error) {
            console.error('Smooth scroll init failed:', error);
        }
    }
    

    
    function initReadingProgress() {
        try {
            const progressBar = document.getElementById('reading-progress');
            if (!progressBar) return;
            
            const updateProgressBar = debounce(() => {
                const winScroll = document.body.scrollTop || document.documentElement.scrollTop;
                const height = document.documentElement.scrollHeight - document.documentElement.clientHeight;
                const scrolled = height > 0 ? (winScroll / height) * 100 : 0;
                progressBar.style.width = scrolled + '%';
            }, 16);
            
            window.addEventListener('scroll', updateProgressBar, { passive: true });
            updateProgressBar();
        } catch (error) {
            console.error('Reading progress init failed:', error);
        }
    }
    

    function initPageLoadingState() {
        try {
            document.addEventListener('click', (e) => {
                const link = e.target.closest('a[href^="/"], a[href^="https:&#x2F;&#x2F;veradec.xyz&#x2F;"]');
                if (link && !link.target && !link.getAttribute('download')) {
                    document.body.classList.add('page-loading');
                }
            });
            
            window.addEventListener('pageshow', () => {
                document.body.classList.remove('page-loading');
            });
        } catch (error) {
            console.error('Page loading state init failed:', error);
        }
    }

    function init() {
        initNavigation();
        initScrollToTop();
        initPageLoadingState();
        
        
        initCopyCodeButtons();
        
        
        
        initSmoothScroll();
        
        
        
        initReadingProgress();
        
    }

    if (document.readyState === 'loading') {
        document.addEventListener('DOMContentLoaded', init);
    } else {
        init();
    }
})();</script>