Uploaded November 2025 | Updated September 2026, 2 weeks ago

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In our quest to run Microsoft BASIC on the MMD-1, we add an Altair-compatible serial port using a vintage MC6850 chip.

MMD-1 Playlist: youtube.com/playlist?list=PL-_93BVApb5_ITRdT7BjqpjQfCqc58O-g
Project Documentation: curiousmarc.com/computing/mmd-1-intel-8080-trainer

Stuff that supports the channel:
- Support us on Patreon: patreon.com/curiousmarc
- Amazon links for the tools I use in the lab: curiousmarc.com/amazon-links
- Channel merch on Fourthwall: curiousmarc-shop.fourthwall.com
- Legacy channel merch on Teespring (I don't have everything transferred to Fourthwall yet): teespring.com/stores/curiousmarcs-store

"Elevator Music" Credit: Crinoline Dreams by Kevin MacLeod

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- PCBWay: fast turn PCBs, pcbway.com
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- Samtec: connectors: samtec.com
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Get more technical info on the companion site: curiousmarc.com
Contact info: youtube.com/curiousmarc/about