6502

163 Articles

The Bit79 Was A Famicom Clone That Took The “Family Computer” Name Seriously

July 6, 2026 by 10 Comments

While the original name of what much of the world knows as the NES was the Nintendo Family Computer, or Famicom for short, it was very rarely used as a family computer. Sure, there was a basic cartridge and an add-on keyboard sold in Japan, but it was always a sideshow to the games.

Nintendo recognized that when they brought their Entertainment System overseas. Most of the various famiclones — which date back to the mid-80s — are the same. BIT in Taiwan had a different idea: their Bit 79 would be a full home computer. Picture a C=64 that plays Nintendo games, and you might not be too far off. [Inkbox] tells the full story in his latest YouTube video, and it’s a must-watch for anyone interested in the history of 8-bit machines that are totally unknown in the West.

Continue reading “The Bit79 Was A Famicom Clone That Took The “Family Computer” Name Seriously” →

A 6502 All In The Data

April 15, 2026 by 12 Comments

Emulating a 6502 shouldn’t be that hard on a modern computer. Maybe that’s why [lasect] decided to make it a bit harder. The PG_6502 emulator uses PostgreSQL. All the CPU resources are database tables, and all opcodes are stored procedures. Huh.

The database is pretty simple. The pg6502.cpu table has a single row that holds the registers. Then there is a pg6502.mem table that has 64K rows, each representing a byte. There’s also a pg6502.opcode_table that stores information about each instruction. For example, the 0xA9 opcode is an immediate LDA and requires two bytes.

The pg6502.op_lda procedure grabs that information and updates the tables appropriately. In particular, it will load the next byte, increment the program counter, set the accumulator, and update the flags.

Honestly, we’ve wondered why more people don’t use databases instead of the file system for structured data but, for us, this may be a bit much. Still, it is undoubtedly unique, and if you read SQL, you have to admit the logic is quite clear.

We can’t throw stones. We’ve been known to do horrible emulators in spreadsheets, which is arguably an even worse idea. We aren’t the only ones.

6502 based laptop

Retro Rover: LT6502 Laptop Packs 8-Bit Power On The Go

February 17, 2026 by 9 Comments

Making your own laptop can be a challenging project, but a doable one, especially given the large number of options available today for computing. Of course nothing says you need to use a modern component in your build, and in the LT6502 project by [TechPaula] they didn’t go with a modern RPi or the like, nope went right back to about 50 years ago to use a 6502 at the heart of this DIY laptop build.

The 6502 is an 8-bit microprocessor from the 1970s, found in the Commodore 64 and Apple II. This wasn’t their first venture into 8 MHz world of the 6502, prior to this laptop build there was a desktop build the PC6502 bringing this chip of old into a PC/104 form factor. The LT6502 adds in the things you’d expect with a laptop, a 9-inch foldable screen, a 10,000 mAh battery, several external ports for things such as serial console and USB-C charging. A custom keyboard adds in low-profile switches as well as including a HDSP-style 8-character display, a great addition for a modern take on this vintage chip. Onboard there is 46 KB of RAM and with the addition of the CompactFlash for storage the LT6502 runs EhBASIC which we’ve seen before in some other great projects.

The case is mainly 3D-printed safely enclosing the custom PCBs for both the keyboard and motherboard, and providing a satisfying glow with the built-in LEDs within. All of the files are up on the project’s site so be sure to swing by and check out both this and the desktop PC/104 predecessor to it. Great job [TechPaula], looking forward to seeing the future installments on the LT6502 such as implementing the included internal expansion slot.

Vintage Canadian Video Hardware Becomes Homebrew Computer

February 14, 2026 by 7 Comments

Are you in the mood for a retrocomputing deep dive into the Scriptovision Super Micro Script? It was a Canadian-made vintage video titler from the 80s, and [Cameron Kaiser] has written up a journey of repair and reverse-engineering for it. But his work is far more than just a refurbish job; [Cameron] transforms the device into something not unlike 8-bit homebrew computers of the era, able to upload and run custom programs with a limited blister keypad for input, and displaying output on a composite video monitor.

Continue reading “Vintage Canadian Video Hardware Becomes Homebrew Computer” →

2025 Component Abuse Challenge: The VIA Makes Noise, Again

November 14, 2025 by 3 Comments

In the days of 8-bit home computing, the more fancy machines had sound chips containing complete synthesizers, while budget machines made do with simple output ports connected to a speaker — if they had anything at all. [Normal User] appears to be chasing the later route, making PCM sound by abusing the serial port on a 6522 VIA chip.

A serial port is when you think about it, a special case of a one-bit output port. It’s designed for byte data communication but it can also carry a PCM data stream. We’ve seen this used with microcontrollers and peripherals such as the I2S port plenty of times here at Hackaday, to produce such things as NTSC video. The 1970s-spec equivalent might not be as fast as its modern equivalent, but it’s capable of delivering audio at some level. The machine in question is a Ben Eater breadboard 6502 with a World’s Worst Video Card, and as you can hear in the video below the break, it’s not doing a bad job for the era,

If you think this hack sounds a little familiar then in a sense you’re right, because Ben Eater himself made noises with a 6522. However it differs from that in that he used the on-board timers instead. After all, the “V” in “VIA” stands for “versatile”.

Continue reading “2025 Component Abuse Challenge: The VIA Makes Noise, Again” →

Photo of breadboards and bench oscilloscope

Programming The 6581 Sound Interface Device (SID) With The 6502

November 10, 2025 by 6 Comments

Over on YouTube, [Ben Eater] pursues that classic 8-bit sound. In this video, [Ben] integrates the MOS Technology 6581 Sound Interface Device (SID) with his homegrown 6502. The 6581 SID was famously used in the Commodore line of computers, perhaps most notably in the Commodore 64.

The 6581 SID supports three independent voices, each consisting of a tone oscillator/waveform generator, an envelope generator, and an amplitude modulator. These voices are combined into an output filter along with a volume control. [Ben] goes into detail concerning how to configure each of these voices using the available facilities on the available pins, referencing the datasheet for the details.

[Ben]’s video finishes with an 8-bit hit from all the way back in October 1985: Monty on the Run by Rob Hubbard. We first heard about [Ben’s] musical explorations back in June. If you missed it, be sure to check it out. It seems hard to imagine that demand for these chips has been strong for decades and shows little sign of subsiding.

Continue reading “Programming The 6581 Sound Interface Device (SID) With The 6502” →

Optimizing A QuickTake Image Decoder For The Apple II’s 6502

October 5, 2025 by 7 Comments

The idea of using the Apple II home computer for digital photography purposes may seem somewhat daft considering that this is not a purpose that they were ever designed for, yet this is the goal that [Colin Leroy-Mira] had, requiring some image decoder optimizations. That said, it’s less crazy than one might assume at first glance, considering that the Apple II was manufactured until 1993, while the Apple QuickTake digital cameras that [Colin] wanted to use for his nefarious purposes saw their first release in 1994.

These QuickTake cameras feature an astounding image resolution of up to 640×480, using 24-bit color. Using the official QuickTake software for Apple Macintosh System 7 through 9 the photographs in proprietary QTK format could be fetched for display and processing. Doing the same on an Apple II would obviously require a bit more work, not to mention adapting of the image to the limitations of the 8-bit Apple II compared to the Motorola 68K and PowerPC-based Macs that the QuickTake was designed to be used with.

Targeting the typical ~1 MHz 6502 CPU in an Apple II, the dcraw QTK decoder formed the basis for an initial decoder. Many memory and buffer optimizations later, an early conversion to monochrome and various other tweaks later – including a conversion to 6502 ASM for speed reasons – the decoder as it stands today manages to decode and render a QTK image in about a minute, compared to well over an hour previously.

Considering how anemic the Apple II is compared to even a budget Macintosh Classic II system, it’s amazing that displaying bitmap images works at all, though [Colin] reckons that more optimizations are possible.