rnd:sketchpad

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rnd:sketchpad [2024-02-13 01:54] – asdfrnd:sketchpad [2024-10-01 05:10] (current) – asdf
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 ====== Sketchpad ====== ====== Sketchpad ======
 A home for project ideas that aren't yet fully formed (and which may never be). Those that do survive this gestation phase should receive their own pages, and rejects should probably be retained somewhere. A home for project ideas that aren't yet fully formed (and which may never be). Those that do survive this gestation phase should receive their own pages, and rejects should probably be retained somewhere.
 +
 +===== Teensy softcard for Apple II =====
 +Build an Apple II softcard based around the Teensy microcontroller. I'm not yet sure what we'll do with it yet, but we should try to keep as many special pins (the main I2C/SPI buses, maybe a UART bus) free for later use. Maybe one corner of the initial card could be a protoboard, or we could have some of the free pins broken out for jumpers to a breadboard. Sample projects for inspiration:
 +
 +  * https://github.com/rallepalaveev/A2DVI/blob/main/v2.0/A2DVI.v2.0.sch.pdf
 +  * https://www.tindie.com/products/cvt/esp32-softcard-expansion-card-for-the-apple-ii/
 +  * https://www.v2retrocomputing.com/analog (can be used as a VGA output //or// a Z80 softcard!)
 +  * schematics and details in the MS SoftCard manual
 +
 +We don't yet have a specific use case in mind. Some ideas:
 +
 +  * I2C/SPI/UART interface
 +  * some kind of audio card/MIDI thing?
 +  * ProDOS disk emulation (via SD card)
 +  * Z80 softcard
 +  * ethernet?
 +  * USB bus sniffer
 +
 +It may make sense to start with a very simple breakout card and a basic bus sniffer firmware. 
  
 ===== Dual Euclidean trigger/gate module with logic ===== ===== Dual Euclidean trigger/gate module with logic =====
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 Selectively mute and mix different components of a MIDI stream.  Selectively mute and mix different components of a MIDI stream. 
  
 +**This already exists!** It's called the [[:sounds:MRCC]], and I have one. 
 ===== 8800 Lisp interpreter ===== ===== 8800 Lisp interpreter =====
 Why not? I like the Altair, and I like Lisp. Some starting points: Why not? I like the Altair, and I like Lisp. Some starting points:
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 ===== Microcontroller-based LLDP sniffer ===== ===== Microcontroller-based LLDP sniffer =====
 +//See [[.:projects:tnt]]//
 +
 This would be a great combination with [[.:projects:aft]]. I've discovered that most switches at work source LLDP packets, which can be helpful to identify where a given cable ends up. Having a device that could capture these packets and decode fields of interest would be extremely handy. This would be a great combination with [[.:projects:aft]]. I've discovered that most switches at work source LLDP packets, which can be helpful to identify where a given cable ends up. Having a device that could capture these packets and decode fields of interest would be extremely handy.
  
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 } }
 </graphviz> </graphviz>
 +
 +Also take a look at the [[https://www.hfsignals.com/index.php/ubitx-v6/|uBITX]] and [[https://www.vu2ese.com/index.php/2022/07/20/the-sbitx-the-sdr-for-the-homebrewer/|sBITX]]. These are homebrew multi-band superheterodyne transceivers built around an Arduino/Teensy and a Raspberry Pi, respectively. Each project includes detailed schematics, block-by-block circuit descriptions, and firmware/UI explanations. Both also use the Si5351 clock generator to produce the local oscillator(s). 
 ===== Email pingback ===== ===== Email pingback =====
 Sometimes it's handy to know when someone opens an email.  Sometimes it's handy to know when someone opens an email. 
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  • Last modified: 2024-02-13 01:54
  • by asdf