Finance64

A 1982 computer, talking to the internet, on its own

Type a US ticker symbol on a Commodore 64. The machine reaches out over its own network connection, fetches the quote, and draws it.

There is no PC involved. No gateway, no proxy, no companion program running on a modern machine, no cloud account, no API key. The C64 speaks to the data provider directly. When a price appears on that screen, a forty-year-old computer went and got it.

The display is a real VIC-II 320×200 high-resolution bitmap — the price line is a genuinely plotted curve, not text characters arranged to look like one.

What it shows you

• Company name, last price, and the day's move in money and percent
• Open, previous close, high, low, volume, P/E, market cap in human units (457M, 4.67T), and the 52-week range
• Day charts of the live session, minute by minute, during US market hours
• Week and Month charts of the last twenty closes
• A volume histogram under every chart showing how much changed hands in each slice — not a running total
• A watchlist of up to eight companies, fetched in a single request and saved to the disk you ran it from, so your list travels with the disk
• Auto-refresh — one keypress turns the machine into a desk display that updates itself every minute

What you need

• A Commodore 64 Ultimate, or a C64 with a 1541 Ultimate-II / II+ cartridge
• The cartridge's network working, with an IP address
• The Command Interface enabled in the cartridge settings

Finance64 carries no networking of its own — it asks the Ultimate to make the connection. A standard C64 cannot run it, however modern the modem attached to it. Today's Wi-Fi modems give the machine a fine internet connection but speak a different language from the one the Ultimate speaks.

In the download

• finance64.d64 — disk image; your watchlist saves onto the same disk
• finance64.prg — the program alone, for a USB stick or the Ultimate's menu
• Finance64-Manual.pdf — eighteen pages: every screen, every field explained, and an honest chapter on what it will not do
• README.txt, LICENSE.txt

Being straight with you

Prices are delayed public data, not a professional feed. US symbols only. Eight watchlist slots. Twenty points per chart. No news, options, alerts or portfolio tracking. The feed is a free public endpoint that owes nobody anything and could change without notice.

The connection is plain HTTP, because this hardware cannot manage modern encryption. The only thing your machine ever sends out is the ticker symbol.

This is not a trading tool and must not be used to make financial decisions. It is a program built for the pleasure of watching an old computer do something it was never designed to do.

Licence

Free to share, don't resell. Copy it and give it away complete and unmodified as much as you like.

Made with

Written in C for the 6502, with AI assistance, and a great deal of stubbornness about fitting a bitmap chart, an HTTP client and a JSON parser into 64 kilobytes.