--- title: 2026 Retrocomputing Challenge: Explore Space With A... description: A 1990s TRANZ 330 credit card terminal has been reprogrammed into an interactive solar system guide. The device is built around a Z80 processor, and its... canonical: https://daily.dev/posts/2026-retrocomputing-challenge-explore-space-with-a-credit-card-reader-wdoaycwlz twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: 2026 Retrocomputing Challenge: Explore Space With A Credit Card Reader | daily.dev og:description: A 1990s TRANZ 330 credit card terminal has been reprogrammed into an interactive solar system guide. The device is built around a Z80 processor, and its... og:url: https://daily.dev/posts/2026-retrocomputing-challenge-explore-space-with-a-credit-card-reader-wdoaycwlz og:image: https://api.daily.dev/og/posts/WDOaycwlZ.png og:image:alt: 2026 Retrocomputing Challenge: Explore Space With A Credit Card Reader og:image:width: 1200 og:image:height: 630 og:locale: en --- > ## Documentation Index > Fetch the complete documentation index at: https://daily.dev/llms.txt > Use this file to discover all available pages before exploring further. # 2026 Retrocomputing Challenge: Explore Space With A Credit Card Reader **[Hackaday](https://daily.dev/sources/hackaday)** · 2 min read · 0 upvotes · 0 comments ## Summary A 1990s TRANZ 330 credit card terminal has been reprogrammed into an interactive solar system guide. The device is built around a Z80 processor, and its UV-erasable ROMs made loading custom code straightforward. CharlesD mapped the display, keypad, and serial interface, then connected a modern GPS module and an era-appropriate thermal printer. The new code computes azimuth and elevation for a given planet, giving an offline solar system map. Source code for the project has been shared publicly. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Questions this post answers ### What kind of processor is inside an old Verifone TRANZ 330 credit card terminal? The TRANZ 330 credit card terminal is built around a Z80 processor, making it essentially a complete Z80 computer rather than a dedicated payment device. It uses UV erasable ROMs, which makes loading custom firmware onto the unit straightforward once its display, keypad, and serial interface have been mapped out. _Retrocomputing hackers track oddball hardware teardowns like this one on daily.dev._ ### How can I turn an old point-of-sale terminal into a custom embedded project? One approach, demonstrated on a Z80-based TRANZ 330 terminal, is to reverse-engineer the display and keypad, then use the serial interface to connect new peripherals like a modern GPS module and the terminal's original thermal printer. Custom math routines can then compute outputs such as planet azimuth and elevation for an offline solar system guide. _daily.dev surfaces hands-on embedded hacking projects for developers repurposing old hardware._ ## Similar posts on daily.dev - [A Computer Terminal The Old Way](https://daily.dev/posts/a-computer-terminal-the-old-way-66kkumcxj) · Hackaday · 0 upvotes · 0 comments - [Z80 Membership Card & Microcomputer Kits](https://daily.dev/posts/z80-membership-card-microcomputer-kits-6exsllnfn) · Hacker News · 0 upvotes · 0 comments - [Someone made a literal credit card-sized ESP32 computer, and so can you](https://daily.dev/posts/someone-made-a-literal-credit-card-sized-esp32-computer-and-so-can-you-b1x1lp4ln) · XDA Developers · 0 upvotes · 0 comments - [2026 Retrocomputer Challenge: Vectron65 Plus Puts The Emphasis On Plus](https://daily.dev/posts/2026-retrocomputer-challenge-vectron65-plus-puts-the-emphasis-on-plus-y3idbdrf8) · Hackaday · 0 upvotes · 0 comments --- Tags: [#hardware](https://daily.dev/tags/hardware), [#embedded](https://daily.dev/tags/embedded), [#retrocomputing](https://daily.dev/tags/retrocomputing) [View this post on daily.dev](https://daily.dev/posts/2026-retrocomputing-challenge-explore-space-with-a-credit-card-reader-wdoaycwlz) ```json {"@context":"https://schema.org","@graph":[{"@type":"Organization","@id":"https://daily.dev/#organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180},"sameAs":["https://twitter.com/dailydotdev","https://github.com/dailydotdev","https://www.linkedin.com/company/daily-dev-ltd"]},{"@type":"WebSite","@id":"https://daily.dev/#website","url":"https://daily.dev","name":"daily.dev","publisher":{"@id":"https://daily.dev/#organization"},"potentialAction":{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https://daily.dev/search?q={search_term_string}"},"query-input":"required name=search_term_string"}}]} {"@context":"https://schema.org","@type":"TechArticle","headline":"2026 Retrocomputing Challenge: Explore Space With A Credit Card Reader","url":"https://daily.dev/posts/2026-retrocomputing-challenge-explore-space-with-a-credit-card-reader-wdoaycwlz","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/2026-retrocomputing-challenge-explore-space-with-a-credit-card-reader-wdoaycwlz"},"datePublished":"2026-10-27T20:33:19.294Z","dateModified":"2026-10-27T21:01:02.903Z","description":"A 1990s TRANZ 330 credit card terminal has been reprogrammed into an interactive solar system guide. 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It uses UV erasable ROMs, which makes loading custom firmware onto the unit straightforward once its display, keypad, and serial interface have been mapped out. Retrocomputing hackers track oddball hardware teardowns like this one on daily.dev."}},{"@type":"Question","name":"How can I turn an old point-of-sale terminal into a custom embedded project?","acceptedAnswer":{"@type":"Answer","text":"One approach, demonstrated on a Z80-based TRANZ 330 terminal, is to reverse-engineer the display and keypad, then use the serial interface to connect new peripherals like a modern GPS module and the terminal's original thermal printer. Custom math routines can then compute outputs such as planet azimuth and elevation for an offline solar system guide. daily.dev surfaces hands-on embedded hacking projects for developers repurposing old hardware."}}]} ```