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Posts Tagged ‘7400’

A 7400 frequency counter, on perfboard

Monday, April 9th, 2018

jaeblog published a new build: I like perfboard, especially the ones with plated trough holes. But I also like SMD components, and more and more fun IC’s are not available in DIP. So a while ago I designed some perfboard with 1.27mm pitch, making some SMD parts like SOIC stuff...

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Posted in DIY | 4 Comments »

Nibbler 7400 4-bit custom CPU demos

Monday, September 30th, 2013

[embed]http://www.youtube.com/watch?v=fVoNWT34Yt0[/embed] Steve at Big Mess o’ Wires writes: I finished building my 7400 computer, and posted some demo videos here Via the forum.

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Posted in project logs | 1 Comment »

Nibbler 7400 4-bit custom CPU update

Monday, September 2nd, 2013

Steve at Big Mess o’ Wires posted an update on his Custom 4-Bit CPU: Enough with the vague design talk – here’s the circuit schematic for the Nibbler 4-bit CPU! Click the image to zoom in to a full size view. For simplicity, this version omits some details like bypass capacitors, clock...

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Posted in project logs | No Comments »

Nibbler: Another 7400 4-bit custom CPU

Wednesday, August 28th, 2013

Steve at Big Mess o’ Wires writes: I know the Open 7400 Contest is long past, but I wanted to call out a new 7400-based custom CPU I'm building. It's a 4 bit CPU called "Nibbler", and more info is on my web site here My goals are to keep the...

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Posted in project logs | 3 Comments »

Blast from past: Automatic shutdown timer for TVs

Thursday, October 4th, 2012

Back in the 80s when very few TVs had remotes, let alone automatic shutdown timer, Victor decided to build exactly that for his grandfathers TV. After a set interval an LED turns on indicating that the timer has expired, if a button isn't pressed within a few seconds the TV...

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Posted in DIY | No Comments »

DIY 6502 computer using block transfer engine

Friday, September 7th, 2012

Andre Fachat has written a post on his 6502.org blog detailing his DIY 6502 computer build. "I have built a DIY 6502 computer, which is mostly TTL logic only except for 65xx chips and ROMs, but the most TTL-ish part is the blitter: A block transfer engine that DMAs memory...

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Posted in CPLD, DIY, vintage | 1 Comment »

Workshop Update for July 4th, 2012

Wednesday, July 4th, 2012

UPS package finally corralled, and will be delivered tomorrow. A 74HCT245 will complete a long-delayed final revision of a certain secret prototype. We prepared for tomorrows workshop video on serial port interfacing. We arranged a giveaway for a coming week, and perhaps the first sponsor of the 2012 Open 7400...

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Posted in Workshop Update | No Comments »

Workshop Update for June 12th, 2012

Tuesday, June 12th, 2012

Today we renewed websites, including 7400contest.com which is coming up again soon. We patched an SPI speed error in the Bus Pirate binary access mode. We had to cancel the company credit cards because 7 unexpected charges to Blizzard (World of Warcraft) and 4 to iTunes showed up today. In...

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Posted in Workshop Update | 3 Comments »

7400 Contest: 24 hours left

Thursday, October 20th, 2011

Reminder to all those interested in entering their projects into our Open 7400 Logic Competition: Entries must be received by October 21, 2011, 6AM GMT. You only have 24 hours left to send your entry in. Entering Entries can be posted on in our forum, on your personal blog, or even a handy...

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Posted in 7400 contest | 2 Comments »

Open 7400 Logic Competition: Only two days left to enter!

Wednesday, October 19th, 2011

Reminder to all those interested in entering their projects into our Open 7400 Logic Competition: You only have two days left to send your entry in. Entering Entries can be posted on in our forum, on your personal blog, or even a handy how-to site like Instructables. When you’re ready,...

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Posted in 7400 contest | 5 Comments »

7400 competition entry: SPI LCD backpack

Friday, October 14th, 2011

Stephen added his entry in the Open 7400 Logic competition, he made a LCD backpack that uses the SPI interface. Using two 74LS595 serial to parallel shift registers connected in series, he successfully sends data to the 16x2 LCD and adjusts the backlight brightness, by sending 2 bytes over the SPI. The first byte to be...

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Posted in 7400 contest | No Comments »

New 7400 Competition sponsor: YourITronics

Tuesday, September 6th, 2011

YourITronics is the latest sponsor of the Open 7400 Competition. Prizes include a CP2103 serial to USB adapter with GPIO, TMP275 Digital Temperature Sensor and MPL115A2 pressure sensor breakout. Get your entry in and this and other cool hardware can be yours.

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Posted in 7400 contest | No Comments »

Recent Comments

  • Joe Desbonnet: Ya, I can recommend the low melting point solder. I used brand 'ChipQuik' and it's amazingly easy to use.
  • Jerome: I need a new BusPirate for the Fablab ;) Many thanks!
  • Max: Seems like an unexpectedly violent way to remove the chip indeed. A hot air station should of course do the job just fine, but in...
  • jose: Part removal described here is pure butchery, the cheapest hot air station will do a fast and clean job removing the QFP, heat air to...
  • Cody: Yes please