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Teensy Loader For Mac4/19/2021
To perform a hard reset hold the reset button in for 20 seconds with power, continuing to hold the reset button but remove the power for 20 seconds, and finally connect the power while still holding in the reset button.If youre not much of a touch typist (or keyboard geek) youre probably not aware that modern (inexpensive) keyboards are an abomination unto typing.
Their enduring popularity and sometimes surprising price tag on the second hand market is testimonial to their design and build quality. They even offer an uber-geeky blank keycap variant to totally confound your visual based two fingered typing coworkers. Due to their specialist and somewhat niche market however these keyboards cost twenty times that of a cheap membrane keyboard. NeXT used a proprietary communication protocol to link their keyboard and computer, and early Apple did exactly the same thing with Apple Desktop Bus (ADB) an early ancestor to our modern day device independent USB protocol. Whilst there have been various commercial ADB to USB adapters produced over the years building one from scratch proved to be a much more satisfying experience. They saved me hours of reverse engineering and hardware sniffing and made this project a breeze. Teensy Loader Code In ConfigPresumably because I was using a newer version of the compiler than the author I received a build error: make: objadbusbcommonxprintf.o Error 1 which was rectified by modifying the code in config.h to include a new conditional key combination for command ifndef ASSEMBLER include adb.h include matrix.h define ISCOMMAND() ( matrixison(MATRIXROW(ADBPOWER), MATRIXCOL(ADBPOWER)) ) endif Be sure to keep the original endif below the code block when pasting the patch. As I placed the board inside my keyboard case (now you see why size is important) I didnt need any further modifications. Other people modifying this keyboard who placed a significant length of wire (such as an ADB cable) between the keyboard and Teensy needed a pullup resistor between the signal and power lines. I had to use a 1K resistor when testing using a breadboard and external cable, but after placing the Teensy inside the keyboard with virtually no wire length it became unnecessary. If you need a pullup resistor (in the 1-10k range, you may need to experiment) it will link ADB pins 1 and 3. ![]() I had a bit of difficulty tracing the ADB pin outs this time as it was a slightly different keyboard (Apple Extended) A great reference is the ADB Apple Desktop Bus pinout. Specifically this line: sudo dd bs1m ifDownloads2012-10-28-wheezy-raspbian2012-10-28-wheezy-raspbian.img ofdevrdisk3 What ended up solving the problem for me (after much hair pulling) was to not use the built in SD card reader of my MacBook Pro, and to use a cheap external USB dongle. There are plenty of other articles to discuss the merits of decreased latency benefits of a CDN or the effects of parallelism on browsers so it wont be covered here. Teensy Loader Download A CopyIf youre hosting jQuery locally then your users must download a copy at least once. Your users probably already have multiple identical copies of jQuery in their browsers cache from other sites, but those copies are ignored when they visit your site. When a browser sees references to a CDN-hosted copy of jQuery it understands they all refer to exactly same file. The browser trusts that those files are identical and wont re-request the file if its already cached. It seemed nothing had changed and during transport from one location to another it had simply died. ![]() ![]() It was not to be however, and many hours were about to be spent solving the problem.
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