MicroVGA: 5 Simple Ways to Add VGA Output to Microcontrollers

I found my first MicroVGA module in a dusty parts bin at a liquidation sale in Toledo. Five bucks. The guy running the booth had no clue what it was. “Some kinda video thing,” he said. I recognized the SECONS logo immediately. Paid cash. Walked away grinning like an idiot.

That was 2019. I had just left my job at a plant in Detroit where we’d been using these little boards to build custom monitoring stations. Nothing fancy. Just green text on black backgrounds showing pressure readings and temperature logs. The kind of display that makes a maintenance tech’s life easier.

Here’s the thing though. When I got home and plugged that $5 find into an Arduino Mega, it worked perfectly. Crystal clear 80×25 text. Zero configuration drama. And it hit me: we take simple solutions for granted until they vanish.

MicroVGA was that solution. A $30 board from a Czech company called SECONS Ltd. that turned any microcontroller with a UART port into a proper text terminal. No framebuffer. No GPU. Just two wires and ANSI escape codes.

And yeah, I know what you’re thinking. VGA in 2026? Honestly, I get it. HDMI runs the world now. But walk onto any factory floor in the Midwest and you’ll still see VGA ports on half the monitors. Industrial equipment doesn’t care about your consumer tech trends. It cares about what works.

Why Most VGA Solutions Are Overkill

Look, if you just want a screen for your Arduino project, the internet will drown you in bad advice. Reddit is full of people telling you to buy a Raspberry Pi 4 and call it a day. “It’s only $35!” Yeah, and it draws 3 amps, needs a heatsink, and takes thirty seconds to boot. For a sensor dashboard that just needs to show four numbers?

Not even close.

The other common suggestion is a small LCD. SPI TFT panels are cheap now. You can get a 2.4-inch color screen for eight bucks. But try reading that from five feet away on a noisy shop floor. Squinting at tiny fonts while wearing safety glasses isn’t my idea of usable design. Been there. Hated it.

Then there’s the “roll your own VGA” crowd. Bit-banging VGA timing on an AVR chip. Technically possible. I’ve seen the projects. Some kid on YouTube will show you how to output 640×480 from an Arduino Uno using nothing but resistors and prayer. What they don’t show is the 90% CPU usage just to keep the sync signals alive. Your main program? Forget about it. The microcontroller becomes a very expensive video card.

And that’s when I realized the real problem. Everybody wants to sell you complexity. What nobody talks about is the middle ground. A dedicated, simple text output that doesn’t eat your processor cycles. That’s exactly what the old SECONS module provided. It handled all the VGA timing internally. Your microcontroller just sent text characters over a serial line at up to 1.25 million bits per second.

PS/2 keyboard input built right in. S-Video output for old CRT TVs. 16 colors. 80×25 text mode. All for less than the cost of a decent lunch.

The frustration isn’t that good solutions don’t exist. It’s that the simple ones keep disappearing while everyone chases features nobody asked for.

What MicroVGA Actually Does Under the Hood

The module itself is tiny. About the size of a postage stamp if postage stamps had VGA connectors and MiniDIN ports. SECONS designed it back in 2008 as a universal way to add human-readable output to embedded projects without redesigning your whole board around a display controller.

Here’s how it actually works. The board contains its own video signal generator. It outputs standard SVGA at 800×600 resolution and 60 Hz refresh rate. But internally, it renders an 80-column by 25-row text buffer. Each character cell is 10×24 pixels. That gives you the classic terminal look — white (or green) text on a black background — without your microcontroller ever touching a single pixel.

Communication happens over UART or SPI. UART mode needs just two wires: TX and RX. At the default 1 Mbps baud rate, you can fill the entire screen in milliseconds. SPI mode is even faster if you have the pins to spare. Both interfaces run at 3.3V TTL levels, so it plays nice with modern ARM chips, ESP32s, and of course classic 5V Arduinos.

The control protocol is pure ANSI/VT100. That means if you’ve ever written a terminal program, you already know how to use it. Send \x1B[2J and the screen clears. Send \x1B[31m and your text turns red. Move the cursor, set colors, draw boxes. The conio library that SECONS provided made it even easier — you could call clrscr() or gotoxy() just like the old DOS days.

Power consumption sits around 150 milliamps at 5V. Not nothing, but reasonable for a device generating its own video timing. The board auto-detects whether you’ve plugged in a VGA monitor or an S-Video cable. It even handles the 75-ohm termination detection to switch between PAL and NTSC television standards automatically.

The PS/2 keyboard port is a nice touch most people forget about. You can build a full interactive terminal without adding any other input hardware. A technician in Ohio I talked to at a Maker Faire in 2018 had built a complete machine controller using nothing but an ATmega328, one of these boards, and an old Dell keyboard he pulled from a dumpster.

Want the full technical background on how VGA signaling works? Wikipedia’s VGA article breaks down horizontal sync, vertical sync, and why the 15-pin D-sub standard became the baseline that made modules like this possible.

Price back in the day? €23.90 for a single bare unit. About $29.95 USD. A five-pack dropped the per-unit cost to roughly $24.95. In 2010, that was a bargain. Today, adjusted for inflation, it would be around $42. And people still hunt for them.

Speaking of hunting — let me tell you about the secondary market. Because SECONS stopped production years ago, you’re not buying new. eBay occasionally shows used units from European sellers. Expect to pay €40–€60. No warranty. No support. Just a board that might work. I bought one from a guy in Germany last year. Looked fine. Had a cold solder joint on the blue channel that tint everything cyan. Spent an hour reflowing it. Worst mistake ever was trusting a photo.

How We Used It in a Real Factory

In 2017 I was consulting for a small parts manufacturer near Detroit. They had an old CNC lathe from 1998. Great machine. Solid iron. But the original CRT monitor had died, and the proprietary replacement cost $2,800 from the OEM. The owner laughed at that quote. “For a screen? I’d rather have my guys read dial calipers.”

I proposed something different. We added a simple pressure transducer and a thermocouple to the coolant system. Fed the data into an Arduino Mega. Wired a MicroVGA board to an old Dell LCD monitor we found in their IT closet. Total parts cost under $60. The Mega read sensors every second, formatted the data into a clean text table, and sent it over UART to the display.

The result looked like something from a 1980s sci-fi movie. White text on black. Real-time coolant pressure. Temperature. Spindle RPM pulled from a hall effect sensor. A simple alert flag when pressure dropped below 30 PSI. Nothing graphical. Nothing animated. Just information a machinist could read from across the room without squinting.

The plant manager loved it. Not because it was pretty. Because it prevented three coolant-failure incidents in the first six months. Each incident used to cost them two hours of downtime and a scrapped part. The simple text display meant the operator saw problems coming before they became expensive.

We built three more stations. All using the same setup. The SECONS boards made it trivial. No graphics library to learn. No framebuffer memory to manage. Just printf statements routing to a serial port. A junior tech could modify the code.

Here’s where it gets interesting. In 2019, one of the boards failed. Coolant mist got inside the enclosure through a bad gasket. I went to order a replacement and found the red “out of stock” message on SECONS site. That project died not because the concept was bad, but because the hardware became unobtainium.

If you’re curious about how other hardware setups compare for connecting devices to displays, I also wrote about how to connect a PS5 controller to a PC — different problem, same principle of finding the simplest working path through a tangle of bad advice online.

What I Use Now Instead

Since you can’t buy new MicroVGA hardware, you need a replacement. I’ve tested four options extensively. None are as plug-and-play, but all are cheaper and actually available.

Option 1: Raspberry Pi Pico with PicoVGA

This is my daily driver now. The RP2040 chip on a $4 Pico board can generate real VGA signals using nothing but GPIO pins and a resistor ladder. The PicoVGA library by Miroslav Nemecek gives you full bitmap graphics, sprites, and audio output. Resolution ranges from 256×192 up to 1280×960.

I built a digital readout for a milling machine last spring using this setup. Eight GPIO pins. Twelve resistors costing maybe $0.60 total. An old VGA cable I cut open. The whole video output circuit fit on a scrap of perfboard smaller than a credit card.

The catch? You’re writing C or C++. No simple UART text commands. You allocate a framebuffer. You draw pixels or load fonts. It’s more powerful but steeper. If you want code examples and wiring diagrams, the PicoVGA GitHub repo has everything from Mandelbrot renderers to raycasting engines.

Option 2: ESP32 with bitluni’s Library

For Wi-Fi projects, the ESP32 is unbeatable. Bitluni’s ESP32Lib uses the I2S peripheral to generate VGA signals. Supports 800×600, 14-bit color, hardware sprites. I used this for a wireless weather display in my workshop. Total cost? About $7 for the dev board and resistors.

The community around this library is massive. His YouTube tutorials have millions of views. Reddit threads troubleshoot common issues. If something breaks, someone already fixed it. That’s worth something when you’re debugging at 11 PM before a deadline.

Option 3: Dedicated TFT with Controller

Sometimes the best replacement isn’t VGA at all. A 7-inch SPI TFT with an ILI9341 controller costs $12 on Amazon. No external monitor needed. No cables. Just mount it to your enclosure. For portable or compact projects, this often makes more sense than driving a separate screen.

I use these for handheld test equipment. The downside is the small size and the need to write graphics code rather than simple text streams. But libraries like LVGL make it manageable.

My Honest Pick for Most Projects

If you need VGA output specifically — maybe you’re retrofitting old industrial monitors or building a retro computing project — go with the Pico. The $4 board and free library beat hunting for discontinued hardware. For new designs where screen size doesn’t matter, use a TFT. Skip the ESP32 unless you need wireless. It’s overkill for a simple display.

For a broader look at how hardware evaluation works, check out my HP Pavilion 13 notebook evaluation — I approach every hardware review the same way: real use, real flaws, no marketing fluff.

What I Got Completely Wrong

I need to confess something. When I first heard about PicoVGA, I thought it was a toy. “Bit-banging VGA from a $4 microcontroller? That’s gonna look terrible.” I was wrong. Dead wrong.

My first PicoVGA build output a stable 640×480 image on a Dell monitor I found in recycling. Colors were crisp. Sync was solid. I had assumed dedicated hardware like the old SECONS board would always produce cleaner signals. Nope. The RP2040’s PIO state machines are so deterministic that the timing is actually more precise than some old dedicated chips.

But then I made the real mistake. I assumed all monitors would accept the same signal. They don’t.

I shipped a PicoVGA project to a client using a 2009 AOC monitor. Black screen. Nothing. Drove 40 minutes to troubleshoot. Checked wiring. Checked code. Everything perfect. Plugged into my test monitor — worked instantly. Back to the AOC — dead.

Turned out that ancient monitor had picky horizontal sync polarity. The default PicoVGA config used one polarity. That monitor demanded the other. Most modern LCDs auto-detect and adapt. Older ones? Not so much. One line change in the config fixed it. HSyncPol = 1 instead of HSyncPol = 0. Three hours of my life I’ll never get back.

The old SECONS module never had this issue. They tested against every monitor they could find. That’s the hidden cost of rolling your own — you become the compatibility lab. Dedicated hardware costs more because someone else already suffered through the edge cases.

Does Text-Only VGA Still Matter in 2026?

Here’s the thing that surprises people. VGA isn’t dead. Not even close.

Walk into any manufacturing plant, medical device lab, or point-of-sale back office. VGA ports are everywhere. HDMI and DisplayPort won the consumer war, but industrial equipment has a thirty-year lifespan. Those monitors stay in service until they physically break. And when they do, replacements with VGA inputs are still manufactured because the demand exists.

According to market data from 2024, the global microcontroller market sits at roughly $22 billion and keeps growing at nearly 7% per year. That means more embedded devices, more need for simple human interfaces, and more situations where a basic text terminal is exactly right. Not everything needs touchscreens and animations. Sometimes you just need a number that a tired technician can read from six feet away.

The MicroVGA approach — dedicated text output over serial — solved a real problem elegantly. It was the right product at the right time. The fact that it disappeared says less about the idea and more about how hard it is to sell simplicity in a market obsessed with features.

Yeah, I know. A $30 board that only does text sounds primitive next to a full-color TFT. But primitive isn’t the same as useless. A hammer is primitive. It still drives nails better than a Swiss Army knife.

If you’re maintaining legacy equipment that used the SECONS module, you have two choices. Hunt eBay for used units and pray they work. Or redesign around modern alternatives. Honestly? Redesign. The Pico costs less than a used MicroVGA and does fifty times more. The only thing you lose is instant VT100 compatibility, and that’s a weekend of coding to recreate.

And if you somehow find one of those old boards in a parts bin at a flea market? Buy it. Wire it up. Enjoy the simplicity. Just don’t build your company’s future around hardware you can’t source.

Arduino’s official blog covered the original MicroVGA back in 2010 when it first gained traction with makers. Their write-up shows how early the embedded community recognized the value of simple serial-to-video bridges. Reading it now feels like looking at a blueprint for something we took for granted.

Frequently Asked Questions

Can you still buy a MicroVGA module new?

No. SECONS Ltd. lists the product as out of stock until further notice, and that notice has not changed since roughly 2019. The official website still hosts documentation and PDF datasheets, but the ordering page shows no available inventory. Used units appear rarely on eBay or in forum classifieds at prices between €40 and €60, but those come with no warranty and uncertain condition.

What is the cheapest replacement for a MicroVGA today?

The Raspberry Pi Pico with PicoVGA is the cheapest path. The Pico board retails for $4. The resistor network costs under $1. No additional modules required. For a basic text terminal, total cost stays under $5. An ESP32 with bitluni’s library runs slightly more at around $6–$7 total but adds Wi-Fi capability if your project needs network connectivity.

Do modern alternatives require understanding VGA timing signals?

Not for normal use. Both PicoVGA and ESP32Lib handle horizontal sync, vertical sync, blanking intervals, and color encoding internally. You write to a framebuffer or text buffer, and the library pushes pixels to the monitor. The only time you adjust timing manually is when you hit a compatibility issue with an unusual or very old monitor, which is rare.

Is VGA completely obsolete for new designs?

In consumer electronics, yes. HDMI and DisplayPort dominate TVs, laptops, and monitors sold after 2015. But in industrial, medical, and embedded applications, VGA remains common because of legacy hardware and the simplicity of analog signaling. Many monitors manufactured between 2005 and 2018 still include VGA inputs, and some current industrial displays continue to offer it as a legacy option.

Can the old MicroVGA module work with a modern LCD monitor?

Yes. Any monitor with a VGA input accepts the 800×600 signal the module outputs. LCDs scale the image to their native resolution. The text remains readable, though not as sharp as a digital input would provide. Avoid trying to use VGA-to-HDMI adapters unless they are active converters with built-in scaling — cheap passive adapters often fail with low-resolution sources.

What happened to SECONS Ltd.?

SECONS s.r.o. appears to have ceased active product development around 2012. Their website copyright stops at 2008–2012, and no new products or updates have appeared since. The company may have pivoted to other engineering services, been acquired, or simply closed. Without official announcements, the exact status is unclear, which is common for small European electronics firms serving niche embedded markets.

Should beginners start with a used MicroVGA or a modern alternative?

Start modern. A used MicroVGA teaches you nothing about current embedded development, costs more than a Pico, and provides no community support. The PicoVGA and ESP32 ecosystems have active forums, example code, and YouTube tutorials. The learning curve is steeper than plug-and-play UART text, but the skills transfer directly to every other project you build afterward.